All posts by Mike Dimmick
Below are all of Mike Dimmick's postings, with the most recent are at the bottom of the page.
Son in Law: The SDN multiplex, which carries ITV3, is at full power since last week's retune.
The prediction at SP8 4AD is much better than that at SP8 5PY, so I would expect something different in the receiving set-up.
C48 is in Group C/D, but only just. If the aerial is quite old it might not work very well down at that frequency - the groups were extended to squeeze in Channel 5 when it launched in 1997. It might be worth going wideband now, as there may be new services as far down as C33 (although this has not yet been finalized).
This frequency hasn't ever been used before at Mendip. If this is a residential block with a communal aerial - bird's eye view on Bing suggests it might be - it could be a channelised system and the system would require retuning to amplify this channel rather than the previous location. The levels might need to be recalibrated too, even if it isn't channelised.
The overall signal levels are substantially increased since last week, and that could push a system that was working into having too much signal. See Freeview signals: too much of a good thing is bad for you | ukfree.tv - independent free digital TV advice for more information. (SP8 4AD) (SP8 4AD)
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Mr. J Talboys: This can often happen if you use the 'automatic search' facility and the box has run out of permanent storage memory. Or, some boxes apparently don't overwrite the permanent locations with this facility.
At major retunes you are recommended to reset the box to a blank state, using the Factory Reset, Default Setting, 'Reinstall All Channels', Full Retune, First Time Installation or Virgin Mode options. Different equipment calls it different things. There are retune guides for some equipment, and full manuals for some others, at TV Re-tune .
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sam: If it's an oval-shaped mesh dish, it's probably set up for the digital satellite services targetted at the UK. If it's older than 2001, it could be aimed at the Astra 1 cluster of satellites that was used for analogue signals before 1998 (these were switched off in 2001).
If it is the right dish, you can just plug in a Freesat box and it should work.
A dish can always be moved to point at a different cluster, and some viewers - particularly in northern Scotland - were recommended to get larger dishes or fully circular ones, so this isn't a sure-fire test of being able to just plug in and go. You can adjust the dish yourself with the help of tools like UKSatelliteHelp.co.uk - Satellite Dish Alignment / Setup Calculator 2.0 , but you may need a meter for best results.
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Cavendish: Digital UK's postcode predictor gives you an excellent chance of getting a full service from the Belmont transmitter in north Lincolnshire. This transmits Yorkshire local news. The probability of reliable results from West Runton is shown as substantially lower and is expected to deteriorate after September 2012; it is your best option for BBC Look East and ITV1 Anglia, however.
You should actually be able to get four out of the six multiplexes from Belmont now; the other two are on low power to avoid interfering with services from Tacolneston. You would need a wideband aerial for all six once they power up, which happens after Tacolneston switches over.
Relay transmitters are usually directional, transmitting most of their power in one or two directions. Unfortunately, we don't know what the radiation pattern is. Given the distance between you and the transmitter, and the relatively high power level, I have to assume that there is quite a high restriction in your direction.
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John de Carteret: See Will there ever be more services on the Freeview Light transmitters? | ukfree.tv - independent free digital TV advice for an explanation of why relay transmitters only carry some channels.
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Graham Booth: Lower quality values after DSO - assuming that it's a grade out of 10 - is often an indicator of too much signal. See Freeview signals: too much of a good thing is bad for you | ukfree.tv - independent free digital TV advice for more information.
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Looks like Channel 4 HD will be moving to Astra 1N when it gets into position:
News - SES.com
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Briantist: Sudbury has a retune on 16 November. To clear C50 for Tacolneston, ArqB moves to C63.
http://www.digitaluk.co.u….pdf
It will remain at 2,200 watts.
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Steve P: That information is out of date. It came from an Ofcom document (licensing section) that has been superseded and wasn't consistent with a different Ofcom document ('stakeholders' section). All sources now agree that ArqB has moved from C63 to C39, now that Emley Moor's early HD service is no longer in the way.
mycloud: Given you are practically on top of the Sheffield (Crosspool) transmitter, you probably do have too much signal. See Freeview signals: too much of a good thing is bad for you | ukfree.tv - independent free digital TV advice .
Do be sure that you have done a full factory reset, exactly as you should have done at switchover; many boxes simply can't handle a multiplex moving to a different frequency using the 'add channels' function.
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Clive Jenner: I got that when Hemel Hempstead retuned a few weeks ago (14 September). HH simply retransmits what Crystal Palace transmits, so a change in the frequency information for HH had to actually be transmitted by CP.
I also have a PVR-9200T, but it hasn't prompted again since. Are you up to date? If you press MENU and go to System, Status, the versions should be:
System ID: 3020.0000
Application Version: PGXTF 1.00.23
Loader Version: A4.09
Update Date: 20th May 2010
If the versions are older than that, the current version is currently being rebroadcast. In the Software Update menu, make sure that it is set to automatically update at 4am. Make sure you put the receiver in standby before you go to bed, it will not update unless it is in standby.
That said, I think the change notification was only added in the that version.
As I recall, there are three options, Now, Later and something else. I pressed whatever would cause it not to retune at all, and never ask again (i.e. the third option).
Humax do recommend doing a Default Setting after installing that update. You might try doing one anyway. That will delete the future recording schedule and all channels, and all other settings - previous recordings are kept. I'd particularly advise moving the RF output away from its default as it clashes with analogue Channel 5 - I've set mine to UHF 53.
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Mary: At that location, chances are extremely good that you have too much signal even without a booster. If you were much further away, I would say that maybe the reflector is too short, but you should be able to use an indoor aerial at that location (or no aerial at all) and still have excellent results.
A wideband is completely unnecessary at Crystal Palace and it's unlikely that it ever will become necessary.
Remove the booster completely, it won't be doing anything useful and could be harming the signal quality.
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Stan Hill: Mendip has never previously used C48 or C52. If you are using a communal aerial, the distribution system might need retuning to amplify these channels instead of the old locations. If you had a similar problem in January when ArqB moved to C67, that's probably the issue now.
You might also or alternatively have another box, such as a Sky box or VCR, with an RF output on a clashing channel, most likely C43 or C47. RF outputs clash with the same channel, adjacent channels, and 5 and 9 channels higher. If you do, try turning it off if it's not used, or retuning it to C21 - this channel is unlikely ever to be used at Mendip.
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Stan Hill: 813 isn't a standard location for any channel. BBC News should normally be on 80. Anything stored in the 800s is a duplicate of something else, and the order they get stored will depend on the order they are found or the relative strength, when you retune.
It could be an indicator that your box doesn't handle the larger Network Information Table, or other extended service information, correctly. Digital UK have a partial list of equipment known to have problems at http://www.digitaluk.co.u…tnit and more information for specific boxes at Digital UK Retail - Troubleshooting guides .
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Chris.SE: A minor quibble, Oxford did not get a temporary mast to provide services while the main antenna was re-engineered. Instead the reserve antenna was used for all services. This is fitted *below* the FM radio broadcast aerials, which occupy a significant amount of space - the reserve is 55m lower down a 159m mast than the main antenna. This is the last resort should a future problem take out the main antenna or transmitters. The main antenna itself is designed in two halves and can be run on only one half, although (presumably) at reduced power. This redundancy is carried through to the combiner unit.
Unlike many sites, at Oxford, low-power DTT ran from the main antenna, plus an extra 'hat' on top of the old cylinder, with the possibility that a couple of multiplexes (1 and B) had an extra filler on the side of the mast, a little below the new reserve. That meant DTT was also quite seriously affected when the main aerial was being replaced.
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KB: Lyngsat says Novasports are on Hotbird 8/9, 13°E. Encrypted using Irdeto 2 - you can get an Irdeto CAM to plug into a free-to-air receiver at a number of UK websites (or at least they're priced in pounds).
Funny how UK channels are on a satellite further east than the Greek channels!
Nova are well aware of this situation, they carry the English commentary (which I believe is the Sky commentary!) on a second audio stream. All adverts and match build-up and review are in Greek (or were a couple of years ago).
It does test your knowledge of the Greek alphabet to figure out which channel is showing your team's match... as I recall, it was in the two seasons when I was interested.
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Suzanne: At 13km from a 100 kW transmitter you need a 14-element Yagi, tops. A 'contract' 10-element would probably have been fine. An indoor aerial will probably work well enough at this location.
I have to say that aerial looks pretty flimsy.
The difference between C60 and C59 at the moment is only 9 dB, there was a much bigger difference between adjacent analogue and digital channels before switchover (e.g. Channel 4 on C53 and Mux B on C52 differed by 19.2 dB).
The problem is that digital TV requires any amplification to be very linear - including automatic gain control and the internals of the tuner. If not, you get intermodulation - frequency-shifted copies of the signal in one channel, that then interfere with another channel. Most amplification circuits are approximately linear - near enough for reliable performance - in their designed input range. Go outside that range and they distort. It's that intermodulation that I think is happening to you.
IF your fitter had set up the signal levels at the recommended level for analogue, they should not now be so strong as to cause intermodulation. However, many fitters either set up the signals at the maximums for low-power digital, despite the large difference in levels between analogue and pre-switchover digital at Oxford, or just fitted the same aerial everywhere regardless of the requirements of the location.
Some boxes might have trouble with very different signal levels between multiplexes, say if their gain control circuits set the level based on the overall signal level, but then I would expect all the commercial multiplexes to fail, not just one. I didn't see very many reports of problems at Sutton Coldfield between stage 1 and 2 of DSO, which had the new BBC multiplex booming in at 200 kW on C40 and the old ITV1 mux (Multiplex 2) at 8 kW on C41 - a difference of 14 dB.
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R Lees: It's cost.
In 2007, the two transmitter owners, Arqiva and National Grid Wireless, published Reference Offers for Network Access, basically sample contracts for transmitting a multiplex. In those documents, the public service broadcaster outline costs - in 2005 prices - were given as £24.7m per multiplex per year, while the commercial multiplex operators were quoted £10.4m. If the costs were shared equally across all six multiplexes, each would pay £17.5m, so an increase of £7.1m (+69%) for the commercial operators, for an increase of potential viewers of only 8.8%.
There are 80 main transmitters and 1,074 relays. The main transmitters are higher-power, but there's a substantial capital cost of equipment required at each relay site.
No, the licence fee is the same, there is no rebate. The licence is for operating or installing a television, the money raised goes mostly to the BBC, and the BBC's public-service channels are all broadcast from all transmitters.
The BBC does own - through BBC Worldwide - half of UKTV, which runs the Dave, Yesterday, Really and G.O.L.D. channels on Freeview, plus a few more on satellite. The revenue from advertising feeds back into the BBC public-service broadcasting budget.
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Richard: I'm not sure what Mendip clash you're talking about, Mux 2 at Oxford was adjacent to Mendip Mux D before switchover, and the two stations ran like that for ten years since March 2001. Both got subsequent power increases, Oxford in August 2002 and Mendip some time in mid-2003. From January this year, Mendip C67 had a power increase from 10 kW to 26 kW so ArqB could launch in final mode, restoring Sky Sports. This would presumably be the upper limit that could be used.
People out in Swindon might have had a problem on occasion with adjacent channel interference (caused by filtering being imperfect - in the real world, some leakage into adjacent channels is inevitable - and a little cost-saving on using less complex filters where there isn't an adjacent channel at the same site). Someone in or near Beckley itself would be unlikely to have this problem except in incredibly rare weather conditions.
I'm really not sure what your issue was - some local source of interference does seem the most likely. If you're having increased problems now - the same on all multiplexes - I'd look into sources of impulse interference like a thermostat or other motor.
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Mike Bryce: Most likely explanations are either an overlap, with the box tuning in the wrong transmitter, or too much signal. See Digital Region Overlap and/or Freeview signals: too much of a good thing is bad for you | ukfree.tv - independent free digital TV advice .
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BobH: Existing recordings are preserved when you use the 'Default Setting' option, which is recommended with major retunes. In the latest firmware 1.00.23, 'Automatic Search' is supposed to be equivalent for retuning, but I still found scheduled recordings could be unreliable unless you delete the schedule and re-create it.
Default Setting resets all other preferences, so you will have to reset the output format option (reverts to 4:3 with letterboxing), the UHF output channel, and the recording schedule (that being the minimum that I do).
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M
Nottingham (Nottinghamshire, England) Full Freeview transmitterThursday 6 October 2011 2:54PM
Nottingham
Pixelated: If you had reliable results before switchover, you could have too much signal. I can't advise any more on that or on the possibility of using Waltham without a full postcode.
At NG12 3JL - roughly the centre of Cotgrave - Waltham gives a better chance of reliable reception than Nottingham, or at least will do after the SDN multiplex reaches full power next Wednesday. You would need a wideband aerial for all multiplexes. It looks as though that postcode is shielded slightly by the terrain, so a higher-gain aerial is probably necessary, and I would recommend an outdoor aerial.
ian from notts: Yes, Emley Moor and Nottingham now use the same frequencies for the SDN, ArqA and ArqB multiplexes, since the retune on the 27th. I don't think these are actually co-ordinated so will interfere with each other in some areas.
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John Morris: The cable insulation is plastic and like all plastics, it deteriorates with exposure to sunlight, and can then let damp in. White insulation tends to be affected worse than black or brown.
Cables should be anchored at frequent intervals, including clips over tiles, so that they cannot move in the wind and rub over the brickwork or tiles, which wears through the insulation.
I'd say you should plan to replace cables about every ten years.
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Willie Donaghy: The number of transmitters and power levels for Freeview, before switchover, was necessarily limited to avoid interactions with the Republic. That's why take-up of digital in Northern Ireland has been relatively poor.
It means digital coverage from Limavady isn't anywhere near the analogue coverage area. Four of the digital multiplexes also clash with the Claudy relay. I'm not surprised that it's unreliable out where you are, although Digital UK's postcode checker isn't currently accepting your postcode so I can't see the actual prediction.
Aerials and cables do deteriorate over time with weather exposure, and if water gets into cables, it seriously degrades the cable's performance - and higher frequencies are affected worse than lower ones.
At switchover, the PSB digital transmissions should have parity with the current analogue transmissions, or slightly better. The commercial multiplexes will still only transmit from Divis, Limavady and Brougher Mountain and will be half the power - but that still means they should be nearly the same coverage as analogue, except for a few areas where channels clash with the PSB channels from a relay (Plumbridge and Castlederg).
It looks like switchover is about a year away, stage one on 10 October 2012 and stage two on 24 October. This is based on a leaflet that briefly appeared on Digital UK's website on Friday - my guess is that the announcement is supposed to be on Monday or Tuesday and someone pushed the leaflet out too early.
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K W: I assume you mean Freesat-from-Sky as Freesat does not require a viewing card.
You can set up parental controls on all Sky boxes. See Sky TV | Set up for the manuals for each different type of box, which will show you how to do this.
They do say that the default PIN is the last four digits of the viewing card's serial number - if you don't have the card, and you haven't set the PIN to something else, you will need to contact Sky to find out what it was or to get it changed.
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Phill: Saorview launched at the end of last year.
A Freeview HD receiver should implement MPEG-4 AVC on DVB-T, which is required to receive RT 2 when it's broadcasting in HD, even though at present the UK only uses MPEG-4 AVC on a DVB-T2 multiplex.
For interactive text, the Irish standard permits either MHEG-5 as used in the UK, or the legacy teletext system. Freeview HD equipment is not required to implement legacy teletext.
You can check to see whether the address you'll be using the equipment at is covered by going to Coverage Map | SAORVIEW
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Graeme Young: Yes, BBC A on C61 will have to move, as C61 and C62 are now to be released for 4G mobile in addition to C63-C68 in the original plan. All stations with greater than 1kW ERP output are subject to international co-ordination - although the plan from 2006 shows that Waltham did not need to be co-ordinated with anyone else. Still, the co-ordination required for other sites like Tacolneston, Mendip, Wenvoe (not itself affected directly but it might have to move out of the way of Mendip) means that Waltham is unlikely to make an earlier move than other sites.
C21-C30 are retained for TV broadcasting - they are not going to force the 4.4 million Londoners using Crystal Palace to all buy new aerials (well, unless they're completely mad). The SDN multiplex on C29 is very unlikely to have to move.
You may need to retune the SDN multiplex early tomorrow, as it reaches full power and changes to 8K mode. Changes are supposed to be complete by 6am.
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Craig: Boosters are typically no use whatsoever. They are only of any use if the receiver is particularly noisy, and most Freeview boxes will actually be less noisy than an added booster.
The prediction at your address is 100% across the board, suggesting that the problem is actually too *much* signal. See Freeview signals: too much of a good thing is bad for you | ukfree.tv - independent free digital TV advice .
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Nicholas: The standard Freeview EPG is transmitted on all multiplexes. Each multiplex transmits its own information more frequently than others, and information about programmes coming up sooner more frequently than later events, but it does all get sent and repeat after a few minutes. Some boxes can get very confused with a mix of different services from different transmitters.
I'd start off by doing a full reset or first-time installation with the aerial unplugged, then doing a manual search for the transmissions from your most preferred transmitters. If that is then reliable, do a manual search for just the regional services (BBC A and D3&4) on your second preferred transmitter, which will put those services in the 800s. If it stops being reliable after that, you'll know where the problem lies.
Some equipment does still use a proprietary EPG. Top-Up TV's EPG is attached to TOPUP Anytime 1, Guide+ to bid.tv, and RadioTimes Extra to Television X. All three are on Mux A/SDN.
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Paul: Ofcom's official documentation of Sutton Coldfield's frequencies was re-issued in January this year, to move BBC B's allocated channel from C50 to C40, and ArqB from C49 to C39. This is part of the plan to free C61 and C62 for 4G mobiles - basically C39 and C40 were going to be freed but are now kept. However, a direct move from C62 to C40 or C61 to C39 would affect a lot of people, as they aren't in the same group, so the compromise is *generally* to move allocations of C62 to C50 and C61 to C49, and move C50 to C40 and C49 to C39, where there is a clash.
Yes, this means there will be another retune at Oxford some time in the next two years, to move SDN from C62 to somewhere else, although it *should* remain in Group C/D.
Hannington C50 isn't particularly low at 20kW, that actually made it joint equal most powerful pre-switchover transmitter, with Crystal Palace, Rowridge and Sandy Heath! Post-switchover PSB power levels are only 4 dB higher at 50 kW (COM power levels are 1 dB higher than at present, 25 kW).
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Chrisonahill: The signals from Beacon Hill are at their final power levels. It's unlikely that there will be further power increases.
If your location is still BH20 6JG, I would guess that Rowridge on the Isle of Wight would give better results than either of the mentioned transmitters, once it switches over in March. You're likely to get best results using a vertically-polarized Group A aerial, once the VP services are running at full power from 18 April 2012. The commercial multiplexes from Rowridge will use the same channels as Stockland Hill, which will have some effect, though the use of VP should help (as Stockland Hill is horizontally-polarized).
Your reception of commercial multiplexes from Stockland Hill is liable to be clobbered by Rowridge once it completes switchover, even with Stockland Hill's power increase, and Rowridge's horizontally-polarized COM transmissions being one quarter of the power of VP.
Please note that this is my guess, rather than a prediction from Digital UK, whose website is currently not accepting that postcode.
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John Hodgson: Stow is a 'Freeview Light' transmitter, broadcasting only the public-service multiplexes. The channel line-up should be:
1 - BBC One Scotland
2 - BBC Two Scotland
3 - ITV1 Border Scotland
4 - Channel 4
5 - Channel 5
6 - ITV2
7 - BBC Three
8 - BBC Alba
9 - BBC Four
13 - Channel 4+1
14 - More 4
28 - E4
33 - ITV1 +1
70 - CBBC Channel
71 - CBeebies
80 - BBC News
81 - BBC Parliament
301 - BBC Red Button
and a number of BBC radio stations and text services.
Please see Will there ever be more services on the Freeview Light transmitters? | ukfree.tv - independent free digital TV advice for the explanation (short version: cost).
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Matt: The numbers are the percentage of locations, within the 100m x 100m National Grid square that the centre of your postcode falls into, that are predicted to have (on average) sufficient signal margin to be reliable 99% of the time, and 50% of the time, respectively. It's a measure of the difficulty of locating an aerial within that square and how coverage might vary between you and your neighbour.
The prediction is based on an aerial with CAI Standard 1-class gain, and loss of 3-5 dB in the cable depending on frequency, but the template for cross-polar and front-to-back rejection is weaker than such an aerial would normally achieve. The prediction allows for losses if the signal path goes through a square made up mostly of woodland or of dense buildings but it only allows for average losses. They might be higher or lower than allowed for.
The prediction calculates both the signal from the wanted transmitter and the interference from unwanted transmitters, including adjacent-channel interference.
Short of actually going and surveying every grid square in the country, this is probably the best we can do, but it's always going to give 'wrong' answers for some people.
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Neville Wake: Upscaling cannot create resolution that didn't exist in the original content. An upscaler is only of any use if the upscaler in your TV does a poor job.
Freeview HD channels broadcast (mostly) content that was recorded and processed in HD. The BBC HD channel carries only HD content, the others have a mix of HD and upscaled content depending on how it was sourced. The majority of new programmes are made in HD. The EPG information for BBC One, BBC Two, BBC Three and BBC Four ends with 'Also in HD' if the programme was made in HD and is being simulcast on BBC One HD (for BBC One content) or on BBC HD (Two/Three/Four).
Giles: Ofcom are still deciding what to do with UHF channels 31-37 after DSO completes. The transmitter provider Arqiva have been asked to prepare a Reference Offer for broadcasting up to three new multiplexes using this range of channels; the predicted coverage is lower than for the current six multiplexes. The new capacity could be used for SD or HD channels - that will be up to whoever bids. Ofcom could still decide to release these channels for services other than TV broadcasting.
Over time I would expect the existing multiplexes to be upgraded to DVB-T2 in order to get more capacity from the same spectrum, though DVB-T is likely to remain around for quite a while.
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Briantist: Digital UK's postcode checker is now showing 'COM Mux FEC Change' on various muxes at various sites, over the next couple of months. Hovering over ArqB for The Wrekin shows a change from 64QAM 2/3 to 64QAM 3/4.
It's possible that this will be accompanied by an increase in the guard interval, aiming to improve coverage by turning co-channel interference into SFN; I notice that Hannington and Crystal Palace now show all three COM muxes going to 64QAM 3/4 at switchover, and CP COMs are co-channel with Rowridge. The net capacity is likely to be the same, if that's the case.
64QAM 3/4 8K 1/8 has a fraction more capacity - 24.88 Mbps - than 64QAM 2/3 8K 1/32 (24.13 Mbps).
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Peter Henderson: Digital UK did publish a brochure stating 10th and 24th October 2012 on their website, but the site was reverted to an older version. There could still be an announcement in the next week or so, much longer and it's probably further delayed.
Black Mountain is the old IBA VHF TV mast - Divis was the BBC mast - and has plenty of aperture for a high-power antenna. Channel 5 analogue transmits at 50 kW, apparently from a skew-fire array at the top of the 228 metre mast. A cantilever could perhaps be added if required, or RT could take over the C5 array, depending on how flexible it is and whether it might be needed for MUX 7, 8, 9.
It may be that the new Divis mast wasn't designed to take the weight of the RT mux antenna in addition to everything else, assuming that for whatever reason the PSB or COM main antennas can't be used.
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Andrew Clinton: The only engineering work was this morning, bringing the SDN multiplex up to full power and on the main broadcast antenna. This shouldn't have had any effect on reception of HD channels, unless you were close to having too much signal before, and the additional power on the SDN multiplex has now pushed it over the edge.
See Freeview signals: too much of a good thing is bad for you | ukfree.tv - independent free digital TV advice for more.
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P Smith: Sudbury's next stage is to move ArqB - which carries Yesterday - to C63 on 16 November, to get out of the way of Tacolneston's high-power digital transmissions on C50.
The final channels and power levels will be reached on 27 June 2012, after Dover has stopped using them - the Meridian East region completes switchover on this date.
Digital UK's predictor suggests that your reception of ArqB should be improved when it moves to C63 in mid-November.
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Ian: Sky would waive the fees because they don't want a full investigation into their subscription business. Sky take most of the money off the top of the regular entertainment pack subscriptions and use it to subsidise the sports and movie packages.
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Ian: Sorry, I misread the headline, assuming something that I shouldn't have, that Sky had decided to do so.
The fact is, Sky charge the channels a 'Platform Contribution Charge' which has nothing to do with the costs incurred - it is weighted to the share of viewing. This is actually the majority of the money, the BBC being charged £9.89m overall, £4.78m for BBC One alone. The platform is very well-developed and this charge should be entirely dropped, for all channels.
The actual EPG charges per EPG slot are outrageous too, costing approximately one average worker's salary per slot. I can't believe that it takes anything like that much to manage the flow of EPG data, particularly for the BBC which is very well set up for metadata, since they feed Freeview, Freesat and cable services in addition to Sky.
The regionalization component is something like £2-3m - I couldn't figure out exactly what rules Sky were applying.
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Stuart Dunn, z: Freesat receivers may have a Common Interface (CI) or CI+ slot. This slot takes a Conditional Access Module, which performs the decoding according to the algorithm programmed into it. The CAM requires a card which contains the decryption keys.
Unfortunately, Sky's Videoguard system (owned and operated by a News Corp subsidiary) is not available as a CAM, so you cannot use anything other than a Sky receiver for their services.
z: I'm not sure how a foreign channel got linked to your Sky subscription in the first place.
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Mitchell: Hannington's low-power digital broadcasts are seriously restricted to the north-east, east and south-east. This is because they currently use the same channels as the Guildford analogue transmissions. The main ITV/C4/C5 multiplex - which carries ITV1, ITV1 +1 and ITV2 - uses a less robust transmission mode that is more likely to have problems with this clash.
Digital UK currently show no prediction for five out of the six multiplexes from Hannington, for your postcode.
At switchover, the digital services take over the main antenna, which has no restriction.
You should *not* upgrade your aerial to attempt to get the services. If you do, you are likely to end up with too much signal when it does happen.
Switchover starts on 8 February 2012 - analogue BBC Two switches off, Mux 1 switches off, new high-power BBC A starts on BBC Two's old frequency - and completes on 22 February. The commercial multiplexes remain on the low-power digital antenna until the London DSO on 4 and 18 April 2012, as they still clash with Guildford until those dates.
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Anne White: There are two meanings of 'channel'. One - which this map relates to - is the frequency that the TV service or multiplex is broadcast on. That's the 'UHF Channel' - around here we usually prefix it with a C, e.g. C50. The other is the number you enter to watch a particular service. That's the 'logical channel number'. It's a suggestion that the box is supposed to follow, but if there's already a service stored at that location, it can put the service elsewhere.
With the analogue system, one analogue TV service was transmitted in one UHF channel, so the name 'channel' started to be used for the TV service. Digital services are carried in a 'multiplex', a combination of multiple services in a stream of data, to share some of the overheads of digital encoding and error correction. One UHF channel contains an entire multiplex, which carries anywhere from six to twelve services.
Hannington broadcasts Multiplex 1, which carries the majority of the BBC's digital services, on UHF channel 50. The exceptions are BBC Four, CBeebies and the radio services.
Logical channel number 50 is BBC One HD, at sites that are broadcasting the HD multiplex. This is transmitted in a slightly different way to the other services, which requires 'Freeview HD'-branded equipment. The HD multiplex starts up at the second stage of switchover, except for a few locations that were particularly important to the advertisers (London, Birmingham, Leeds, Newcastle, Glasgow and Edinburgh), where an early service started in 2010. Hannington will start transmitting it from 22 February 2012.
One of the early HD services is from the Crystal Palace transmitter which serves the London area. Some people in the Hannington analogue coverage area can already get HD from Crystal Palace, with the right aerial pointed in the correct direction. I'm not sure it's worth changing with only a few months to go, though.
You will need to retune your Freeview box or TV on 8 February and 22 February. The analogue services shut down, and the high-power digital services take over the old analogue UHF channels. These channels have much less interference than the channels currently used for digital services. Indeed Hannington's digital broadcasts are currently heavily restricted to the east, because the current channels clash with analogue broadcasts from the Guildford transmitter.
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Alan Robinson: If they had reliable reception before switchover, the signal levels could now be too high.
The communal system probably needs adjusting to ensure that the levels on each channel are correct. It might even need replacing if it's particularly old.
See PARAS - Professional Aerial Riggers Against The Sharks for advice on who to contact.
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Steve: You previously said you were at DE4 3ET, is that still the case?
Digital UK don't offer any prediction from Waltham at that address. A look at the terrain shows some very big hills blocking line-of-sight. While signals do refract over terrain, they will always be weaker than if you did have a direct path available.
The Bolehill relay also transmits on C57 and could be generating enough interference to stop the weak signal from Waltham getting through. The problem on C56 is less clear, although it could be down to being adjacent to the HD multiplex from Stanton Moor on C55, and the C57 service from Bolehill.
The broadcasters use antenna diversity - more than one antenna used in an array, or at different heights on the mast - to handle such problems. You *can* do this yourself, but it can be expensive. It's usually a lot easier to go with a satellite service. You can compare the channels available on Freesat, versus Freeview, at Compare Freeview and Freesat TV | ukfree.tv - independent free digital TV advice .
It *is* possible that you have too much signal, which often causes problems for adjacent channels on a transmitter. You did try turning the amplification *down*, not up?
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Briantist: You still have 'Huntshaw Cross B' in the system - the Huntshaw Cross region page puts this on top of Huntshaw Cross, so a click shows a green coverage area and a double-click takes you to the Huntshaw Cross B page.
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Ofcom's 'Table of Digital Stations for Multiplex Licences' shows Mux D on C52 running at 640 watts since 28 September 2011. This is presumably to deal with the added interference from Mendip ArqB moving to this channel on the same date.
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Keith: You'd have to provide a full postcode to see exactly what's available.
The Gorleston-on-Sea transmitter starts to switches to digital on 9 November 2011 (BBC Two switches off, BBC digital services start up), and 23 November (all remaining analogue channels switch off, ITV/C4/C5 digital services and HD services start up). It will be a 'Freeview Light' transmitter, providing only the public-service multiplexes.
The commercial providers are not extending their services to more sites. See Will there ever be more services on the Freeview Light transmitters? | ukfree.tv - independent free digital TV advice .
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Steve P: As I recall, Sky+ cannot perform scheduled recordings from channels in the 'Other Channels' selection, which viewers would have to tune in manually if the BBC were to move off the EPG.
It's a bit of a legal grey area, because the Communications Act 2003 (IIRC) requires the EPG provider to carry the public-service channels, but doesn't say anything about charges.
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Phil: Can you provide a full postcode please?
If anything, Oxford's switchover should have *improved* your reception of Crystal Palace Mux C, because Oxford no longer uses C34. This channel is one of those being cleared for the "digital dividend" so no transmitters have started up digital services on this channel after switchover.
I can't say I'm having any issues with Mux C in Reading, or at least no more issues than before.
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David Rose: At that postcode, this change probably won't give you any more channels. The multiplex carrying Film4, ITV4, Yesterday (ArqB in the list above) moves to a different channel to get out of the way of Tacolneston's switchover; the power level remains the same. If you already get those channels, you will need to retune to keep them. The higher frequency used travels less well, so it's possible that, if your reception of them is a bit marginal, you could lose them or they become less reliable.
The final move is on 27 June 2012, after which Digital UK offer a prediction of 'good' for the SDN and ArqA multiplexes and 'variable' for ArqB. The final channels cannot be used yet as they are still in use at the Dover and Bluebell Hill transmitters.
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spencer: The last update for the Humax HDR-FOX T2 was in June 2011, version FHTCP 1.02.20. If you missed the over-the-air update, you can download it to a USB memory stick, then plug that in to the box to update it.
If you already have that version, you'd have to ask Humax whether they have any updates in development.
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Zak: Is the aerial optimized for Idle? It should be oriented with the elements running up-and-down, not side-to-side, and pointing north-east.
The prediction at the moment is poor, because the low-power services from Bilsdale use the same frequencies as Idle (the three PSB multiplexes and the SDN mux), and the two transmitters are in very nearly the same direction for you.
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Jordy: Denis Wolinski | LinkedIn
Formerly Ofcom chief in Northern Ireland, and before that Northern Ireland head of the Independent Television Commission, Ofcom's predecessor.
Presumably the job was externally advertised due to a policy, but I'd guess there was little chance anyone else would get it!
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Briantist: See Intelsat 907 (27.5°W) - All transmissions - frequencies - KingOfSat .
It carries four national variants of BBC One, one of BBC Two, and all the other parts necessary to assemble both pre-switchover Mux 1 and Mux B (less Sky Sports), and post-switchover BBC A. Significantly it has 301 on there.
In addition, it carries the commercial HD channels ITV1 HD, Channel 4 HD, S4C Clirlun and STV HD, in order to assemble BBC B.
As for the service type identification, I would think that's deliberately wrong to stop your average home decoder from tuning in.
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Fabian: Digital UK suggest that the best option for you is the main Crystal Palace transmitter, which is roughly south-south-east (162°) and 16 km away.
It's very likely that your neighbours' aerials are already facing that direction.
Do be careful of aerials advertised on the Internet and in DIY stores. There is nothing 'HD' or 'Freeview' about any aerial. An aerial *might* be termed 'digital' if it has a balun, a device that better matches the properties of the aerial to the properties of the cable; cheaper aerials designed before digital started might not have had a balun, but an aerial not labelled as 'digital' might still have one.
I assume, by the way, that you're talking about a roof aerial. Indoor aerials can almost never give as good a result as a roof aerial - the elements are always under-sized, UHF signals don't travel well through walls and signals will be attenuated by having to come through neighbours' walls. A small aerial designed for a roof-top can work in a loft, but it's still advisable to put it outside if you can.
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jb38: The only thing I'll add is that the transmitting antennas always have a vertical component to the radiation pattern, the main lobe being aimed at or slightly below the horizon - this is termed the 'beam tilt'. The more tiers in the broadcasting aerial, the narrower this main lobe is. Efforts are made to ensure that there are no nulls.
The beam tilt is basically there to reduce the reflections off the upper atmosphere, causing signals to travel far further than designed - it's also a huge waste of power if much of the transmitted power escapes the intended service area!
The old main antenna at Sutton Coldfield is described in BBC Research Technical Report 1967/19 BBC RD - Publications - R&D Report 1967-19 : UHF transmitting aerial for the Sutton Coldfield television station . The VRP on the south-east face (appropriate for Jack's location) is on p15. At 12km away the angle is about 1.5° below horizontal. At this angle I guess (by eyeball) it delivered about 65% of full strength, which would be about 3.74 dB down (field strength is expressed as a voltage, not power, so multiply the log by 20, not 10). Because it's linear, the graph exaggerates the level of attenuation with increasing angle.
The attenuation in free space is much greater than this, though - using the calculator at Field Strength Calculator gives a value of 12.4 dB difference in path loss for distances of 12 km and 50 km, on C40. Net, the actual field strength at 12 km away is still 8.66 dB greater than at 50 km away.
Of course, we don't know what the VRP of the new aerial is. It may or may not be similar, depending on exactly what coverage area was targetted. Each aerial was a custom build to Arqiva specifications: we know this due to the lead time on the second new aerial at Oxford, after the first was destroyed by fire. They are manufactured by RFS from PHP panels, four to a tier, and standard array patterns are given at the end of http://www.rfsworld.com/d….pdf (the top-mast is two independent 6-tier arrays, one for the PSB multiplexes and one for the COMs).
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Chrisonahill: If you click the number of posts next to a user's name (yours currently says '10 posts'), you can see that user's previous posts. A post attributed to you had a BH20 postcode attached.
Looking at the prediction for your postcode, it still looks like a significant interaction between Stockland Hill and Rowridge. Indeed the prediction for Rowridge VP COM muxes (after April 2012) is still better than for Beacon Hill - ArqA and ArqB, at least.
I can't really see why the prediction for ArqB is so poor, there aren't that many other sites using C51, although one of them is Redruth, which is in the same direction as Beacon Hill and double the distance, and has equal power. The poor predictions for C42 and C45 may be because they're adjacent to the PSB muxes at Redruth.
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Chrisonahill: And C42 and C45 are also adjacent to the PSB transmissions from Weymouth and Charmouth transmitters.
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Dave: Yes, for Freesat. The assumption is that they're only currently encrypted due to rights issues, that they can't broadcast free-to-air across the whole of Europe without paying a lot more money. If that assumption is true, it follows that if they move to a British Isles footprint, it's because they want to go free-to-air.
ITV2, 3, and 4 HD are currently on Astra 2A's north beam - the footprint is at https://sat.ses.com/webse…5753 . The current Freesat channels are on Astra 2D, which only covers the British Isles - see https://sat.ses.com/webse…5243 . Astra 1N's expected UK footprint is https://sat.ses.com/webse…5209 .
The new satellite has 52 transponders which could mean capacity for up to 200 new (or moved) HD channels, though a lot of the frequencies overlap with those already in use on one of the other satellites already in the cluster. We don't know how flexible it is, how many of the transponders can use the UK spot beam and how many can only use the pan-European beams.
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guy: A Freesat box will give you BBC, ITV, C4 and C5 satellite services with no subscription. You can compare the channels available on Freeview (TV through an aerial), Freesat (no subscription, free choice of box), and Freesat-from-Sky (Sky boxes only, requires £££ for recording and time-shifting) at Compare Freeview and Freesat TV | ukfree.tv - independent free digital TV advice .
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MarkR, stevea: I had to resort to watching the F1 on my laptop as both analogue and digital were poor. I think it was down to atmospherics - it was quite foggy on Sunday morning - rather than any work on the transmitter. (I wouldn't want to be up a mast at 6am on a Sunday, would you?)
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Briantist: Chelmsford C5 is a bit of an exception as it belonged more to the London region than to Sudbury, but it went off at Sudbury DSO 2. Still, it *was* an exception.
According to the last timetable published by Ofcom, Channel 5 analogue must switch off by 31 December 2012, but it also still says that for the UTV region as a whole.
I think it's unlikely that analogue C5 from Black Mountain would be switched off before the DSO date.
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Algernon Black: Because the switchover programme is still in progress, a later change at another transmitter can affect some viewers. If they'd switched everything over in one go, this wouldn't have happened - and you'd never have noticed.
Most likely you're in the south or south-east of the coverage area, near High Wycombe, Assendon or Chisbury. Those three transmitters' PSB multiplexes will clash with Oxford's COM multiplexes. The commercial multiplexes are not required to meet any specific level of coverage and certainly not to match the PSB multiplexes, which are required to substantially match analogue coverage.
'Variable' reception in Digital UK's postcode checker does not necessarily mean variable results. It means that using their aerial model, the percentage of locations that should, on average, have reliable performance 99% of the time, is below 70%. It means siting an aerial to get reliable results will be more difficult than if the 'good' standard was met. The aerial model is quite pessimistic, compared to real aerials, regarding rejection of signals from other directions and from the other polarization (those relays will transmit vertically-polarized signals and Oxford uses horizontal polarization).
High Wycombe and Chisbury already use C55/C59/C62 for their analogue transmissions, but a digital service does do more damage to another digital service than an analogue one does. Assendon uses C55 now and will start using C59 and C62 at switchover.
If you do find you are affected, you may be able to fix the problem by rotating the aerial slightly towards or away from the interfering transmitter - real aerials have peaks and troughs in their 'polar response' - how much signal is picked up from different directions - and you may be able to drop the interfering signals into a trough in the response.
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barry: Most likely power to the distribution amplifier failed - perhaps a blown fuse or tripped circuit-breaker? Report it to the landlord or management agent.
At that location, I would expect an indoor aerial to be pretty reliable.
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For reference, VLV is Voice of the Listener and Viewer (VLV)- the campaign for Public Service Broadcasting. and the event was titled "UK Programme Production - Securing its Future".
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Chris Onion: At that postcode, there is a poor prediction for the ArqB multiplex - which carries Sky Sports 1 and 2 - from Waltham. The prediction for Sutton Coldfield is very good.
Digital UK never explain their predictions in detail, but there are a number of relays in the vicinity (Bolehill, Repton, Winshill) that transmit on C57. Levels of signal both from the wanted transmitter and from interfering transmitters do vary over time and not necessarily in line with each other.
If your aerial points south-east to Waltham, you may get better results by pointing south-west to Sutton Coldfield. You would still get East Midlands BBC One and ITV1 from the Derby relay - providing East Midlands service to people better covered by Sutton Coldfield is the reason that it exists.
In both cases you should check that the box has actually tuned in services from the wanted transmitter. See Digital Region Overlap for more information.
Given that the prediction from Sutton Coldfield is 99% across the board, and that you say it was OK before switchover, chances are that if there is a signal level problem, it's too much rather than too little.
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Briantist: Yes, but that's not yet in the Digital UK postcode checker. If the conclusion is that the interference from those relays doesn't significantly affect that many Oxford viewers, chances are that Oxford and those relays will be moved to the same channels.
Ofcom's latest 'Table of Digital Stations' (version 5) now has High Wycombe and Assendon BBC B, and Chisbury BBC A, using C50 rather than C62 from their DSO dates. So perhaps that isn't the source of interference, or not the whole story.
The next nearest transmitter using the same channels is Midhurst, and of course this is a relatively high-power main transmitter using horizontal polarization. The variable reception prediction may just reflect lift conditions. At present C55 is an analogue channel at Midhurst, C59 and C62 are low-power digital multiplexes.
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trevorjharris: The point is not that Sky viewers are having to pay for what others get free, it is that *Sky is charging the broadcasters for what other platforms give away*.
Each Sky viewer costs the broadcasters money, money that they do *not* recoup from subscription revenue. Free-to-air channels don't receive any payments from Sky's subscriptions, nor do 'free-to-view' (encrypted, but available to anyone with a viewing card even without an active subscription). Only the channels actually listed in the Entertainment Pack or Entertainment Pack Extra do. Even for them, Sky's Platform Contribution Charges will often exceed the revenue earned.
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Kate: Sky charge the BBC and therefore the 60% of licence-fee payers who DON'T use Sky a 'Platform Contribution Charge' that Sky use to subsidise their boxes. This charge is related to the percentage of viewing of each channel. It is in no way fair, reasonable or non-discriminatory and should be eliminated.
The charges for appearing in the EPG should be related only to the costs directly incurred in running the EPG, and should be shared fairly between all channels, the PSBs should not be charged more than other channels as they are now. I do not believe that it costs an average worker's salary to maintain an EPG slot, even allowing for other costs of employment - Sky should be forced to account for the actual costs incurred.
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Mark Fletcher: Caradon Hill doesn't use those frequencies, but Rowridge and Crystal Palace will do.
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Mark Fletcher: Sorry, I managed to get Caradon Hill and Beacon Hill mixed up. Still, the reason for Stockland Hill's restriction is more to do with Crystal Palace low-power multiplexes than to do with Caradon Hill high-power.
Yes, there will be some interference between Stockland Hill commercial muxes and Caradon Hill PSBs. In general, though, the more rugged terrain means that there will be less of a clash than between Stockland Hill and Crystal Palace COMs.
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Chris Onion: The only real way to check is to see what UHF channel numbers are in use. I'm not sure, because BT's documentation is maddeningly thin, but these might be displayed in the 'DTT Signal Strength' screen. Try selecting this option when tuned to, in turn, BBC One, ITV1, ITV3, Pick TV and Yesterday and, if available, BBC One HD and see if a UHF channel is listed. Check whether the channel is the same when tuned to Yesterday and to Sky Sports 1.
The channel numbers should match those above for BBC A, D3&4, SDN, ArqA and ArqB respectively (plus BBC B for HD services). If the box has tuned to the Derby relay, you would see C48 for BBC A, C51 for D3&4 and C52 for BBC B (again, if you have HD).
That signal strength screen will also indicate if you have too little or too much signal. If it's showing 100% strength, it's probably too much. If you have a booster, you should remove it. If that doesn't reduce the displayed level or if you don't have one, try adding an attenuator.
If signals were too distorted, the box may have tuned to the Waltham signals instead. Boxes usually tune the strongest, the best quality, or just the first found, depending on the software in the box; however, for you, Sutton Coldfield should be both the strongest and, except for a few multiplexes before switchover and one now (SDN), the first found as well. If the box has tuned to Waltham, you will probably find the signal quality gets worse - do try a full retune following the instructions at How do I scan for Freeview channels? | Help | BT.com Help .
Before switchover, Sky Sports 1 and 2 were carried on the BBC's second multiplex, Mux B. This was on a lower frequency at Waltham than the equivalent service at Sutton Coldfield, so it could be that your box decided to tune that in rather than the SC service - explaining the loss of service when Waltham switched. However, I would expect that to have affected the whole of Mux B (BBC Four and CBeebies, BBC Parliament, BBC radio stations) and not just Sky Sports. Indeed I would also have expected it to affect Mux 2 and A which were also on lower frequencies than the Sutton Coldfield counterparts.
There's a thread on the DTT Signal Strength display at DTT Signal Strength - Technical Question - BTCare Community Forums .
Digital signal levels from Sutton Coldfield were relatively low compared to analogue, so the increase at switchover was very large. The new levels were designed to provide good coverage *without* changing the aerial. If the new, as you say, 'massive' aerial was selected and set up for the pre-DSO levels it could well have led to too much signal now.
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Mark A: Two EPG slots, so two charges. They are also listed separately in Annex 1 due to being audited separately by BARB.
The EPG slots cost £21,000 each; the Platform Contribution Charge is the large bit:
BBC Three: £871,045
BBC Four: £271,615
CBBC: £299,715
CBeebies: £776,750
Assuming that the aggregate viewing figures didn't drop for each segment of viewing, I would assume that the same total would be charged under your scenario as now.
Also, I don't think the BBC channels appear at the same EPG numbers in the Republic of Ireland EPG, so the charges in section B4 probably apply as well.
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Ian Grice: BY LAW Sky, and all other EPG providers, must put BBC One, BBC Two, ITV1, C4 and C5 at the top of their EPG. The idiots who drafted the law forgot to set down any rules about how much the EPG providers are allowed to charge for the privilege.
As previously stated, the majority of the charges are for 'platform contribution' (box subsidy), NOT for carriage in the EPG, although the complexities of different regionalization arrangements for different broadcasters means the number of sub-bouquets - and the charges for appearing in each one - has exploded.
Are YOU happy for your licence fee to subsidise new boxes for new Sky subscribers? I don't object to boxes being subsidised from the subscriber's own subscription fees - a hire-purchase model, like mobile phones - I DO object to the licence fee being hijacked for the purpose.
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I would expect that any frequency changes would be published in the ITU Radiocommunication Bureau's International Frequency Information Circular before Ofcom publish.
http://www.itu.int/ITU-R/…g=en
No indications of channel changes yet.
Where possible - where international clearance was already available for the new channel (due to it being a former analogue channel), or not required due to no interactions with other countries - the changes were implemented before DSO. Emley Moor is shown as having interactions with Ireland. Sutton Coldfield has no interactions listed so a swap of C49 to C39 could be made without affecting anyone else, even though we hadn't asked for it at Geneva 2006. Hannington BBC B could move from C51 to C39 because we had asked for C39, even though there was an interaction with France.
In the GE06 plan, we asked for channels 37, 39, 41, 44, 47, 48, 51 and 52 at Emley Moor, covering all previous analogue allocations, plus the new homes for ArqA and ArqB, all at 52.4 dBW = 173,780 W. C39 was presumably requested for the low-power HD service! It is now in use at Sheffield (the lower power there means it's still within Emley Moor's allocation, technically) in place of the original allocation of C49, to clear that for some other transmitter to use.
You can see that it's a complicated process with a bit of ebb and flow and negotiation required.
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Briantist: In the diagram at the top of the page, you did say Emley Moor 48 to 50 and 51 to 39. Obviously this didn't happen! As you say, it's not now likely to happen unless moving Emley Moor is a pre-requisite for accommodating Waltham or another transmitter using C61 or C62.
For Waltham we asked for 29, 35, 54, 56, 57, 58, 61 and 64, and no international interactions are shown - which does suggest that implementation there is delayed until something else, which does interact, can be moved out of the way.
The mix of what's in and what's not in the plan is odd. Nottingham is in, Stanton Moor isn't, but they have the same power level. It's not that all pre-DSO digital transmitters are in, Idle isn't.
All references are to the GE06 plan as it stood in August 2006, I haven't gone through all the updates to figure out the current state!
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mike Roberts: A number of propogation conditions can mean different frequencies travel more or less well. In general, the higher the frequency, the less it bends over terrain, so you would normally expect - from the wrong side of the Pennines - that the higher frequencies will be less strong than the lower ones. In addition, reflections - causing multiple paths from the transmitter to your aerial - interact differently with different wavelengths (the difference in path length is a different number of wavelengths at different frequencies) and therefore their effect on signal strength can cause changes through measurement.
The power levels as stated are envelope power limits, not absolute limits. In the worst case the different carriers making up the signal could all align the same way at one instant, or all different directions at another instant - the difference between these two conditions is potentially 76 dB! In practice the peak-to-mean ratio is clipped at 7-10 dB, but this is still enough for programme content to mean that different muxes with the same nominal maximum power output read at different levels (source: BBC RD - Publications - White Paper 156 DVB-T and Voltage Ratings of Transmission Equipment ).
Really, the box should measure the size of the pilot and TPS carriers, which do *not* change amplitude (though they do change phase), rather than the whole bandwidth, but that is the customary approach.
Finally, as Brian says, there may be differences in the radiation patterns. The radiation pattern of a full transmitting antenna is made up by combining many smaller elements. The UHF aerial for Emley Moor's second mast (this collapsed before the current tower was built) was eight tiers of 6 panels, each panel carrying 4 elements (8 *components* were fitted to each panel, but the active part was the vertical slot *between* the components, odd as that may sound). Again, the slots behave slightly differently at different frequencies - optimal resonance is achieved at 1/4 of the wavelength, so you can never tune the response of an aerial carrying more than one service perfectly for all of them. The overall radiation pattern is made up by the reinforcing and cancelling signals from each element on each panel.
That original antenna contained transformers to feed only 60% of the power into the two panels in each tier on the south-west face, compared to the other two faces. Pushing any more power into the Pennines was considered a waste. You can see the BBC's report on that antenna at BBC RD - Publications - R&D Report 1966-47 : UHF transmitting aerial for the Emley Moor Television Station , particularly how its radiation pattern differed at C44 (BBC One) and C51 (BBC Two).
Because the Emley Moor tower is now a listed building, the external appearance had to remain the same even while changing the antennas inside the fibreglass shrouds at the top of the mast. In turn, though, that meant that Arqiva didn't have to apply for planning permission to change the antennas as they had at most other sites. So we don't know anything about what the new aerial is like and what its radiation pattern might be.
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Andy: Yes, impulse interference can be a problem. It can be reduced by swapping the aerial for a new one which has a balun, a device that matches the properties of the aerial better to the properties of the cable. Older aerials tended not to have a balun or other matching device.
Aerials meeting CAI Standards 1-4 (which require a balun or otherwise matching to the cable) are usually marketed as 'digital' aerials, though there's nothing inherently digital about them. The testing to actually get the CAI Standard label is quite expensive, so many perfectly good aerials meet the standard but don't get the label. If another aerial in the same family has the label, it's likely this one matches up, the manufacturer just only did the testing for
Log-periodic aerials are inherently balanced and therefore don't need a balun.
You can also improve the screening of the cable - traditional so-called 'low loss' coax cable is now considered anything but. For best results, a dense copper braid screen over copper foil is recommended. This is normally marketed as 'satellite grade'.
You might also try moving your aerial around a little so it no longer points at the road. Aerials have a reasonably wide angle of acceptance before losing a significant amount of gain, so a few degrees to one side or the other may resolve the problem.
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Alan: Digital UK reckon the best transmitter for you, both now and after switchover, is Bilsdale West Moor. It's not that near Redcar; it's actually the other side of Middlesbrough.
Bilsdale transmits currently at 1.6 kW to 6 kW depending on the multiplex, compared to analogue at 500 kW. At switchover the digital signals will be 100 kW for PSB channels, 50 kW for COM channels. These levels are intended to give equivalent coverage compared to analogue for the COMs and slightly more for the PSBs.
The commercial multiplexes will be out of group after switchover, and you will need to change to a wideband or Group K aerial to get them. If you have *already* got a wideband, that might be the cause of some problems as they don't have a lot of gain at the lower frequencies currently used.
Results are currently expected to be variable on Mux 2 - carrying ITV1, ITV1 +1, ITV2, C4, C4+1, E4, More 4 and C5 - and Mux D, which carries Yesterday, ITV4, Film4 among others.
The Seaham transmitter will be 'Freeview Light', carrying only the public-service multiplexes: the BBC's channels, the ones I listed earlier for Mux 2, and the HD services BBC One HD, BBC HD, ITV1 HD and 4hd. By the time the Tyne Tees region has switched, BBC HD may have become BBC Two HD, and a fifth HD service may have joined the line-up.
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C: Sky require a minimum £10 per month payment or they'll disable the recording functions on the boxes. It's quite difficult to find information about paying this fee, Sky would obviously prefer to extract the £20 basic subscription.
Ending your subscription also means you won't be able to time-shift, and you won't be able to play back anything you previously recorded either.
To get full recording features back without paying a subscription, you can buy a Freesat+ box as a drop-in replacement for the Sky box.
Channels that are broadcast without encryption don't require the viewing card, but some regional variants of ITV1, ITV1 +1, ITV1 HD and Channel 5 are encrypted - if you're in one of these regions, that channel will stop working if you remove the card. (Channel 5 has different advertising regions, the programmes are the same.) The region selection is based on the postcode that the viewing card was sent to. There are a couple of other channels that require a viewing card - see Compare Freesat and Freesat-from-Sky TV | ukfree.tv - independent free digital TV advice for the differences in the line-up.
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andy: The Wokingham area suffers from there being a big difference between the analogue and digital signal levels from Hannington. This is a deliberate restriction on the digital output, to protect the analogue services at the Guildford transmitter, and means you can have completely clear analogue pictures and yet unreliable digital.
This flaw was designed into the plan in 1998 and was never lifted despite much investigation of the actual effects on Guildford reception around 2001/2. It will be lifted for the PSBs at switchover (8 and 22 February 2012) and for the commercial multiplexes after Guildford switches (4 and 18 April).
You may get better results from the Crystal Palace transmitter, now and after switchover.
I don't have an explanation why it should have got worse recently, unless a new antenna at Guildford has a different radiation pattern from before (causing an increase in interference) - I can't see any other transmitter that's recently switched over which clashes.
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Howard: Can you confirm which transmitter you're using? If you're trying to use Hannington (aerial would point south-west), you may get better results from Crystal Palace both now and after switchover. The aerial would need to point east-ish for CP, and you'd probably need to replace it as an old aerial for Hannington would be Group E, designed to *reject* signals in the Group A range that Crystal Palace uses.
There are a couple of hills blocking line-of-sight from your aerial to Hannington, which is probably the cause of the problem.
It is worth checking that your box is tuned to the transmitter the aerial is pointing at - see Digital Region Overlap for advice on this.
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mike Roberts: As FM radio is on a lower frequency, it bends more over terrain and so can travel further than UHF television.
The radiation patterns for radio transmitters *are* published by Ofcom, and you can see the one for Emley Moor at FM, MW and LW radio broadcasting | ukfree.tv - independent free digital TV advice . However, The Pulse broadcasts from Vicars Lot, a site several miles to the west and omnidirectional: Vicars Lot analogue radio transmitter | ukfree.tv - independent free digital TV advice .
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Dave Lindsay: The antenna would have been designed to minimize the differences between channels, but it's an inevitable consequence of having multiple channels share one aerial, that the radiation pattern of each channel is a bit of a compromise.
The picture is somewhat exaggerated as engineers normally measure differences in decibels (dB) while those graphs are shown in relative volts. To convert, take the base-10 logarithm of the voltage ratio ('log' on most calculators, LOG10 in Excel) and multiply by 20.
Giving each channel its own antenna at the same site would still be a compromise, as the coverage area is also affected by the aerial's height. Each antenna could be shorter - fewer tiers - to reduce the differences in height, but that would reduce the gain of the aerial and increase the electrical power needed to produce the same output.
In the US, it seems to be common to erect a tower with quite a wide platform that the various antennas then are mounted on - where they do share sites at all. The Empire State Building is festooned with different aerials.
As it is, the commercial multiplexes at Emley Moor are on an aerial slightly further down the mast (about 11.5 metres) than the PSB multiplexes, presumably so that each can be optimized better for the frequencies it's carrying, though it will also offer greater redundancy. The other issue is that the commercial muxes clash more with transmissions from other sites (e.g. Nottingham also uses 48/51/52) and with PSB transmissions from the relay transmitters - both co-channel, using the same channel at both sites, and adjacent-channel interference, due to the imperfect nature of the transmitter - some power leaks into adjacent channels. It is filtered, but filters with a less sharp roll-off are permitted at lower-power sites, therefore more leakage. This only affects the residents near to that site, but it still ends up reducing coverage.
There's a possibility that Emley Moor ArqB might currently be restricted to half power to avoid damage to the low-power Mux 1 at Pontop Pike - there is provision for that in Ofcom's licence documents.
Signal propogation is slightly frequency-dependent, and higher frequencies don't travel quite as well as lower ones, nor carry along cables quite as well. I also mentioned multi-path effects before.
All this put together means you may see different levels across the various multiplexes, and those differences may change over time, despite the published maximum ERPs being identical.
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Mazbar: Channel moves have to be negotiated with neighbouring countries, for the highest-output transmitters. The Geneva 2006 frequency plan for Europe, Africa and the Middle East shows an interaction with Ireland, for Winter Hill.
I'd guess that they will be moved to C49 and C50, on the basis that those channels have been cleared from the Sutton Coldfield and Emley Moor plans. These are still in Group C/D. If those aren't possible, I'm sure great efforts will be taken to keep in Group C/D if at all possible, as Winter Hill has the second-largest population coverage in the country, after Crystal Palace, and just beating Sutton Coldfield.
However, the plans for C31 to C37 are still not finalized; Arqiva have been asked to provide Reference Offers for Network Access for up to three new multiplexes in this space. A wideband aerial would be needed for best results on these frequencies. A Group E might be good enough down at C31, which I see is a possible allocation at Winter Hill. International clearance would also be required for these channels, though, so don't treat those as definite allocations.
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Kate: Ofcom regulates the charges that Sky can charge other providers to carry their sports and movie channels (wholesale charges). It does not regulate the charges that Sky is making for carrying channels in their EPG. That's why we're in this mess.
Encryption is a slightly complicated subject. Encryption can be used for two reasons:
1. To gain access to direct subscription revenue
2. To avoid rights issues that would involve paying more for programmes
The footprints of the earliest satellites in the cluster that carry the UK channels actually cover most of western Europe. You can see them at
ASTRA 2A - SES.com
and
ASTRA 2B - SES.com
(the pages are currently broken, hopefully they'll be back soon). The programme-makers - particularly films and acquisitions from the US - want more money if the broadcasts can be received anywhere in Europe. Encryption segregates the market, only allowing those with a UK viewing card to watch a channel intended for the UK, avoiding this problem.
Astra, with influence from the BBC, launched a new satellite Astra 2D in 2000 with a footprint only covering the UK and Ireland. This allowed the BBC to stop paying Sky to encrypt their channels and broadcast free-to-air. The EXACT SAME UNENCRYPTED transmissions are viewed by Freesat, Sky, and non-branded free-to-air boxes. There is NO encrypted copy of BBC One, Two, Three or Four on this satellite cluster. Later, Channel 4 moved all of their non-subscription channels here and ITV moved most of theirs, and there's also one version of Channel 5. Unfortunately, it's run out of capacity, so the other channels cannot move yet.
Even if you do encrypt, you may not get any revenue. There are 'free-to-view' channels such as 5* and 5 USA, where the operator has decided that ANY current or former Sky subscriber can watch the channel. It's encrypted, and you need a current-generation viewing card and a Sky box (because Sky's encryption method is proprietary), but you don't need an ongoing subscription. Sky call these 'Included Channels' on their website and indicate those that require the viewing card.
Of the traditional PSB channels, only a few regional variants of ITV1 and Channel 5 are encrypted, and those are 'included channels'.
On another page, Briantist claimed that transponder rental is about £4m per year. One transponder carries seven to nine SD channels or variants, or three to four HD channels, or of course a mixture, but on average maybe £500k for an SD channel. That said, there are 18 SD variants of BBC One, £9m.
Sky charge the BBC £5.6m for BBC One being on the platform at all, £25,000 for the EPG slot, and a very complicated charge I haven't fully worked out for regionalization, could be as much as £500k. But that is on top of the broadcasting charges that have already been incurred, for ZERO additional work on Sky's part.
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I should add that there is a new satellite, Astra 1N, designed to provide more capacity for the UK and Ireland channels. One of its broadcast dishes has a footprint covering only the British Isles. It should have arrived at the cluster site in the last day or so, or if it hasn't, it will do soon. The rumour is that some of the 'free-to-view' channels will move across and become free-to-air, no encryption.
Channel 4 HD recently stopped using encryption and moved to the Eurobird 1 satellite which is a little further away, but still close enough to provide coverage. This is Europe-wide. They have decided it's better to pay the extra for content than to continue to pay for encryption. It may well move to Astra 1N once that goes into service, as Channel 4 have agreed to rent space on that satellite.
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Channel 5 have definitely applied. For some inexplicable reason Ofcom's web team have put the application under the Third Invitation to Apply section, rather than creating a top-level Applications Received (Third ITA) section as for the previous two openings.
Ofcom | Third Statutory Notice of Invitation to Apply for DTT Multiplex B Capacity
As expected this is a simulcast of Channel 5 in HD.
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Dave Lindsay: It's helpful to cross-reference with Arqiva's Reference Offer for Network Access from 2005.
Useful documentation
Emley Moor was originally an IBA transmitter so you'll find it under the Arqiva offer, rather than the ex-NGW (former BBC transmitters).
If you look at Appendix 3, List of Main Stations, you'll see that they intended to construct one antenna for the PSBs, and one for the COMs. The reserve antenna can act for the PSBs or for the COMs but not both at once.
My belief is that the two main antennas, PSB and COM, simply sit on top of one another with the PSBs on top, giving the appearance of forming a single antenna. The difference of 11.5 metres is the distance between the centre points of the two antennas (Ofcom use average height). Each antenna is constructed in halves to allow half-antenna running. Each panel is 1.09m in height - if they're using Radio Freqency Solutions' PHP panels - which would suggest 10 tiers, five tiers in each half antenna.
Sandy Heath's data is odd - Ofcom are listing SDN at the same height as the PSB muxes, which doesn't sound right (and the difference between the two is only 2.7m). It would certainly make sense to put 48/51/52 on a different antenna from 21/24/27. Arqiva did project a Class 2 antenna system, each antenna able to offer half-working (at 6 dB down) so I assume that the top 6 tiers are one antenna for PSBs (in 2 x 3 tiers) and the bottom 6 for the COMs.
The reason I say we don't know exactly what's in there is that at other sites, e.g. Winter Hill, the main antenna is a wrap-around of the main lattice structure - I assume RFS PHP12S which have 12 panels per tier - and at others, e.g. Hannington and Dover, the structure has five faces, e.g. RFS PHP5S. At Dover, only three of the five faces have panels fitted, to reduce the amount of power sent into France.
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Briantist: The DTT Allocation Committee could still decide not to allocate any capacity this time around, but I think they'd have to have a very good reason for doing so.
This time, Channel 5 are offering a 24-hour simulcast of the Channel 5 Qualifying Service, although they do say "we wish to reserve the option of exploring possible ways for other providers to make use of some of the day time and late night hours". This was the sticking point last time, that they had said that 6am to 5pm would be an HD service provided by another broadcaster, without stating who that would be.
Of course, last time around, Five was still owned by RTL who were trying to get rid of it, while it's now owned by Richard Desmond's Northern and Shell.
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Dean: Make sure you do a factory reset to clear out all existing stored channels. Your equipment could get confused with ArqB moving to C52 and ArqA replacing it on C67.
C52 has never before been used by the Mendip transmitter, so you need to check all legacy devices like VCRs to ensure that they're not outputting on a clashing channel. Clashes are possible on C52 itself, C51, C53 (due to inadequate filtering), and five or nine channels below, so C43 or C47 - though I would have expected more problems.
The power level is *very* slightly lower on C52 for the moment than it was on C67, but the much lower frequency should result in overall more signal being received for this multiplex. SDN having gone to full power on C48 means that the overall signal level is a lot higher, which could result in too much signal.
Just to confuse things further, the configuration of ArqB will be changed on 8 November - it's not clear whether this is to increase capacity or increase coverage. For you the result is a slightly lower probability of reliable reception, but it's still predicted to be a 98% chance.
Siston is a 'Freeview Light' transmitter and only provides the three PSB multiplexes.
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Nick: Money, and the design of the original licences to broadcast. See Will there ever be more services on the Freeview Light transmitters? | ukfree.tv - independent free digital TV advice for more.
The main transmitter they're using is probably Darvel. If you provide a full postcode we can check whether a full service is expected to be available from this or any other full-service transmitter.
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Briantist: I'd dispute that MPEG Audio Layer 2 audio is better than NICAM 728. Equivalent, possibly, at 256 kbps (the rate the BBC use) but not at 128 kbps as many of the commercial channels use.
Legacy mono audio was FM with a permitted deviation of plus/minus 50 kHz.
Freeview HD audio is AAC-LC (low complexity MPEG-4 Advanced Audio Codec) and I don't know what the bitrate is. Ofcom guessed, for the Second Invitation To Apply, that 192-384 kbps would be used, but bear in mind that this is for 5.1 audio rather than stereo. AAC is generally considered to require half the bitrate of MP3 for the same quality, and MP3 (MPEG-1 Audio Layer 3) itself substantially less than Layer 2.
The *volume* of the audio is nothing to do with it. Layer 2 and AAC can handle the same dynamic range. Indeed they work by hiding noise caused by low dynamic range - caused by saving bits - behind loud sounds. A loud sound at one frequency means that whole sub-band can be encoded with fewer bits.
As I understand it, differences in volume are generally caused by the downmix of 5.1 audio for stereo output. The audio stream carries metadata to tell the receiver what parts of which channel to combine to produce an output only for the front speakers. The crude version is of course to just take the front-left and front-right channels, omitting the contribution from rear-left, rear-right, front-centre and bass channels.
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jgked: Because the wallplates are rubbish? See Satellite, Television, FM, DAB, Aerial, Coaxial Cable, Plugs, Sockets, Connectors & Leads for one installer's opinion on using them and the sort that should be used, if you're going to.
Predicted reception from Wenvoe is already poor, probably due to interference on 42/45/49 from a nearby relay transmitter, and additional signal loss of the wallplate, or noise pick-up, could well push some channels into being too noisy to decode.
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Nicholas Wilmott: It's a '1'-series because its final intended service position is 19.2°E. It's only filling in at 28.2°E until the proper replacements, 2E, 2F and 2G, are built and launched over the next few years.
There is nothing analogue or digital about the satellites, they just relay whatever is transmitted up to them from the ground. The first digital tests at 28.2°E were from Astra 1D, moved there at the end of its service life for that purpose. Astra 1 satellites at 19.2°E (and 2C, which has had a history of being moved here there and everywhere) now carry a mix of analogue channels and digital multiplexes on the various transponders. The remaining analogue channels have been told to move to digital before being shut down next year.
As I said, 2C is at 19.2°E, and could presumably have been moved back to 28.2°E if it was still suitable. However, that only has a single pan-European beam, and the demand is for UK-only footprint. Presumably the UK spot beam got added some time in Astra 1N's construction, too late to push up 2E to an earlier launch.
We still don't know how many of 1N's transponders can use UK-only footprint. In frequency terms, several of the transponders would overlap with Eurobird 1 (28.5°E, close enough to effectively be part of the Sky and Freesat platforms) or with 2A or 2B.
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Gordon Davies: Make sure you're connecting the box to the TV with a digital link, such as HDMI, ONLY. If you connect SCART as well, the TV will often switch to the SCART input due to the box sending the Select signal. SCART is only SD.
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David: An aerial isn't specifically 'analogue' or 'digital', just designed for part or all of the UHF band, though there were some things not often done on cheaper aerials that are recommended for most reliable digital reception.
For HD reception on Freeview, you need a Freeview HD-labelled set-top box, PVR or TV. A PVR is typically required to record, although there are a few TVs you can now plug a USB hard disk into to record. Humax's 'set-top box' HD-FOX-T2 can also be turned into a one-tuner recorder by plugging in a hard disk.
For satellite, you can cancel your subscription to Sky and just use the Sky+ box to receive free-to-air and free-to-view channels. However, Sky will disable the recording and time-shifting functions. You also can't even watch things you previously recorded.
To get recording and timeshift features back, you can get a Freesat+HD PVR. You don't need an additional set-top box. You just plug it in in place of the Sky+ box.
If you're currently distributing the output of the Sky box to the bedrooms, you will also need a plug-in RF modulator as I'm not aware of any Freesat boxes that have one. As an alternative, you should consider getting an additional cable run from the dish to the bedrooms and put a Freesat box in there as well, allowing a viewer in the bedroom to watch something different from the main TV.
You can compare the channels available through a non-subscription Sky+ box ('Freesat-from-Sky'), switching to Freesat, or switching to Freeview, at Compare Freeview and Freesat TV | ukfree.tv - independent free digital TV advice .
If you provide a full postcode we can see whether an aerial change might be necessary to get all channels on Freeview.
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Coupland: Yes, these boxes only supported 2K mode and after switchover, all transmissions (except HD) are in 8K mode.
8K mode was always in the spec, the BBC were particularly keen on it as it allows larger single-frequency networks, but it requires more memory in the earliest stages of decoding so it was cheaper to make a box without it.
onDigital changed to be ITV Digital in 2001, and went into administration in 2002. So the box has to be at least nine years old.
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Duncan Brack: Freesat tuners need an independent connection from the dish to the box. That's because the tuner has to send some control signals back up the cable to the dish, to select low or high frequency range and horizontal or vertical polarization. To cram in more channels, both polarizations are used for different services.
Freesat PVRs usually have two tuners, so you can record one programme while watching another. That requires two connections to the dish. Since the TV itself supports Freesat, you could connect only one of the PVR's inputs if you're short of connections.
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Briantist: Audio description is a secondary mono stream that starts and stops as required. That's true of SD services as well as HD services. For HD, audio description is encoded as HE-AAC - the requirement to use AAC-LC for the main audio stream is that chipsets generally can handle two different streams of AAC at the same time, they can't handle one AAC and one Dolby.
In Ofcom's Second Invitation to Apply, they included a 'Timing of the Fourth HD Service' document:
http://stakeholders.ofcom….pdf
which states (section 3.9) that 32 kbps would be allocated for audio description, in addition to the 192-384 kbps for the main multi-channel audio.
This was obviously before the service launched, so estimates were necessary. The 'Timing of the fifth HD service' document is very thin in comparison, because they're just saying 'the BBC said it was OK'.
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Briantist: Changing the guard interval would not itself improve reception directly (except in rare cases of strong distant echoes, which are unlikely; 7.5km is plenty of distance to prevent this problem). It would improve only if the intent was to synchronize transmissions with another transmitter, in which case the overlap area would have constructive, rather than destructive, interference. It all hinges on the timing.
The nearest candidate using the same frequencies will be Chatton, when it switches over at the end of next year. For that reason, I doubt that it is to do with improving coverage.
Others are certainly reporting that the guard interval has not changed and therefore capacity has increased. The larger capacity is for the moment just carrying more null packets.
On its own, this change will reduce coverage slightly.
The retrofit is due to complete, at least for ArqB, on 23 November (Selkirk, and Tacolneston DSO 2), so we should know more then.
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Andrew Tegala: To be honest I'm surprised they're using Hannington at all. Slough was always considered part of the London TV region, and Hannington has restricted digital coverage to the east at present. Are there any trees or buildings in the direction of the Crystal Palace transmitter that could be blocking reception?
It is possible to combine the signals from two aerials, one pointing in each direction, but obviously that requires extra outlay.
If the system is channelised, it will currently be handling 11 frequencies (5 analogue, six digital) so there will be some spare slots on it after switchover. You only really need the three PSB multiplexes from the other transmitter, the channels on the SDN, ArqA and ArqB multiplexes are all the same throughout England.
Do a survey of your neighbours, see which service they'd prefer and if they'd be interested in receiving both. The management agent will want to recover the cost somehow, of course.
If the aerial was changed, everyone would lose reception until they retuned, so it would have to be co-ordinated carefully.
You should first check that it's not a problem of too much signal on the Crystal Palace services. What do you get on analogue? What does your Freeview box say if you try to manually tune in on C22 and C25? If the signal strength is higher than for Hannington services but quality is lower, it's likely that the signal level is actually too high - this could be considered a fault on the system.
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Tim: That booster? You probably don't need it.
Check that the box has actually tuned to Black Hill transmissions and not something else. The Kilmacolm relay transmitter is very close to you and uses lower frequencies, so could well be picked up when tuning, as older boxes often just store the first signal found when scanning. See Digital Region Overlap for thoughts on how to deal with reception from more than one transmitter.
Otherwise I'd be inclined to assume it's impulse interference caused by the thermostat or other central heating device (pump motor). Does it happen shortly after the central heating comes on?
If none of that sorts it, you can report the problem to the BBC at BBC - Reception problems . Select 'No' for 'Does this answer your problem?' and continue through.
Digital UK, and that BBC page, suggest that you can get a signal from the Strathyre Link transmitter, but I think that's very unlikely. It's probably what you'd expect to get from Black Hill if your aerial was pointing at Strathyre Link. My guess it's treated as a Single Frequency Network in the DUK predictor, but the sole purpose of Strathyre Link is to get the signal down the valley to the Strathyre transmitter itself, and hence is very, very low power (130 milliwatts).
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Tracey: The aerial might be pointing to the Heyshaw relay. This 'Freeview Light' transmitter only provides the channels you've mentioned.
You should be able to get a full service from Bilsdale - both now and after switchover. The chance of a full service from Emley Moor is slightly lower at the moment - the ArqB multiplex clashes with Multiplex 1 at the Pontop Pike transmitter that serves Newcastle. Belmont is also strong enough for a good service on the SDN multiplex as well as the public-service multiplexes.
For Heyshaw, the aerial would be aligned vertically - elements going up-and-down - and pointing west-north-west (291° on a compass). For Bilsdale, Emley Moor or Belmont it would need to be horizontally-polarized - elements going side-to-side. Bilsdale is roughly north-east (32°), Emley Moor to the south (190°), and Belmont south-east (129°).
You, or future tenants, might well be more interested in West Yorkshire news than Tyne Tees, so I'd recommend Emley Moor even though it might be a bit harder to get reliable results from there than from Bilsdale. It's likely that the aerial would have to be replaced, not just moved and rotated, but the cost of an aerial installation is mostly the labour cost anyway.
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Iain: The licensed combinations for ITV1 HD on satellite are:
Central
Granada + Border
London
Meridian + Anglia
Wales + West (+ Westcountry)
Yorkshire + Tyne Tees
That matches the ITV1 +1 regions licensed on satellite and Freeview. They also match ITV1's macro advertising regions. ITV are more interested in getting you the right ads than the right programmes.
However, so far, only Central, London, Granada, and Meridian/Anglia have launched on satellite and Freeview.
To get started quickly, I believe all 'early' Freeview HD services carried London, but they're switching to their own services as switchover happens. You might find that Yorkshire Tyne Tees (Emley Moor news) starts once the London region has switched over in April.
ITV might invest in more variants - including launching the two that they have licences for already - now that more capacity is available on the Astra 1N satellite.
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Ofcom's Table of Digital Stations version 6 has this relay replaced with 'Sunningdale', at the same power and height. This is the name of another building nearby, on Chapelhill Road CH46 9RG.
Wirral Metropolitan Borough Council were notified in May 2010 that the building carrying the Bidston relay was to be demolished: DEM/10/00628 at Wirral Metropolitan Borough Council Planning Pages
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Briantist: Reviewing the older documents, as the NGR in v5 doesn't match this grid reference, the grid reference, height and power were altered in version 5 of the document; only the name was changed in v6 (and the NGR was slightly altered).
New height is 55.3m, 4.8m higher than before, and the new power level is 30W, up from 25W.
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Alan: Signal strength should never hit 100%. You have too much signal already. If you have a booster, get rid of it. You will probably need to add attenuators to get back into range - or just replace the old perfectly good aerial.
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Bob Loader: With a prediction of 100% chance of reliable reception, chances are that you have too much signal. See Freeview signals: too much of a good thing is bad for you | ukfree.tv - independent free digital TV advice .
Another possibility is that your box has decided to tune in the signals from The Wrekin, which also have a predicted 100% chance across the board, as they are on lower frequencies. See Digital Region Overlap for how to resolve this issue.
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Graham: It's quite likely that your box has tuned in ArqB from Sutton Coldfield, on C39, rather than from The Wrekin on C47. See Digital Region Overlap.
I'd second the other suggestions to remove the amplifier. It shouldn't be necessary.
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george: Depends on the box.
Sky boxes will retune automatically whenever Sky change the EPG data. You may need a current viewing card inserted to get the right region, if and when ITV move some ITV1 regions.
Freesat-branded boxes are supposed to retune automatically, but not all do. Some need to be put in standby to do it, or you have to select a retune function. Some viewers found they had to do a factory reset when BBC HD and BBC One HD changed over to DVB-S2 on the same transponder.
Generic free-to-air receivers will need to be retuned manually. Don't do it until the channels disappear from their old location.
The Astra 1N satellite is in the cluster of satellites at 28.2°E. You don't have to move your dish at all.
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Nedbod: The compression will be increased to make space.
trevorjharris: The bit rate will be reduced but the BBC and the other broadcasters are happy that, with improved MPEG-4 AVC encoders, picture quality will not be.
The specification provides a toolbox for how content could be encoded, and information on how to decode it. The difficulty is all in the encoder, how it is able to process the content to most efficiently reduce the redundant data, under near-real-time constraints. Early AVC encoders were basically MPEG-2 encoders not using any of the new tools, just using a few ways of packaging the resulting stream slightly more efficiently.
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NottsUK: My assumption is that everything is still in test, with experimentation on just how much or little forward-error-correction is required, and how reliable use of 8PSK will be. 8-phase-shift keying, as opposed to quadrature phase-shift keying (QPSK), delivers three bits per symbol rather than two, but requires more signal-to-noise ratio for the same error-correcting code rate.
DVB-S2 also defines 16-APSK and 32-APSK, which require multiple amplitudes as well as changing the phase, but I wouldn't expect to see support in domestic receivers, as it's not mandatory.
I'll consider testing ended when a service is deleted from a 2A/2B/2D transponder, or an FTA service appears in the Freesat EPG.
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mrdtv: Depends who you believe. Considering I was getting the same readings percentage-wise on the digital tests as for analogue signals, I'd say it was full power, though of course the digital box isn't designed to measure an analogue signal.
If I'm right about the calibration of my box's strength meter, my usual level for low-power digital at 35% translates to 56 dBuV, while the high-power test at 60% translates to 71 dBuV, or 15 dB higher than current values. The increase at DSO is only supposed to be 10 dB. 15 dB would be near 600 kW.
BBC Two analogue was on noticeably lower power (showing only 40% on C33 on my PVR, though again measured as if it were a digital signal), which was attributed to it running from the back-up transmitter at Croydon.
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Perhaps this is the reason for the increase in capacity on ArqB. Or it could be on ArqA, as I believe the last switched-over transmitter still running Mux C is Sandy Heath, and that will change over to 64QAM 2/3 on 23 November, on its final channel and power level, according to Digital UK's postcode checker.
Either of those options would require a sub-lease from the BBC's pre-DSO Mux B capacity for the regions yet to switch (no chance they launch without London!)
Another alternative is that G.O.L.D. will get kicked off Mux A, as Top-Up TV is ulimately only borrowing Channel 5's capacity, as I understand it. TUTV aren't currently promoting G.O.L.D. as part of their subscriptions.
Channel 5 +1 is very unlikely to join the main channel on Mux 2/D3&4. The precedent is that timeshifts are not treated as qualifying services. Channel 4 +1 and all the regional ITV1 +1s are licenced under Digital Television Programme Service licences. That means that even if ITV and Channel 4 had capacity, they would have to ask Ofcom's permission to carry C5+1. ITV plc lost a slot to allow Channel 5 on in the first place; there is about one slot of spare capacity if Ofcom would get their backsides in gear and kick the remnants of Teletext off the mux, but you'd have to assume that would revert to ITV.
Of course C5 do have a regional advertising structure, which could complicate things.
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jb38: Caldbeck COM muxes are on low power until 24 October 2012, to reduce interference to the low-power digital services at Divis (Mux 1, A and B). Divis completes switchover on 24/10/2012.
Bill: You might be using a Freeview Light transmitter such as Kirkby Stephen - in which case replacing the aerial with a good quality Group A design, horizontally polarized and pointed at Caldbeck, may still produce good results. We need a full postcode to give a better answer.
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Briantist: I've recently been using BCL easyConverter Desktop BCL easyConverter Desktop — PDF to Word Converter — Accurate PDF Converter. to attack Ofcom's PDF files. It says it's PDF-to-Word but it's actually PDF-to-RTF.
I used that, along with Word's Compare Documents feature, to spot the change from Bidston to Sunningdale.
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Peter Henderson: Internationally-cleared frequencies are published in the Geneva 2006 broadcasting plan, and updates to it. The Newcastle site was cleared for 12B, the BBC national ensemble, in May 2009, and Camlough in July 2009. Camlough shows definite agreement from Ireland (and Belgium, France and Holland, since it will contribute to the overall power transmitted by the whole SFN); Newcastle doesn't, but it also doesn't show the countries expected to be affected. No-one appears to have raised a complaint, though.
http://www.itu.int/ITU-R/…g=en is updated every two weeks, though GE06 plans, covering VHF Band III for T-DAB and UHF Bands IV and V for DVB-T, are not updated every time.
In the Reserved Assignments List at Ofcom | DAB Technical Policy Documents , Camlough and Newcastle are both listed as having 'other possible local block usage' on 10C and 12D. 12D is the Northern Ireland local multiplex carrying BBC Ulster. I can't find a reference to use of 10C in Northern Ireland anywhere else, though.
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mike: Did you have digital TV before switchover? If not, you may still have a Group A aerial. For all channels from the Sandy Heath transmitter, you will probably need to change to a wideband type.
The signal levels are expected to be sufficient even with the SDN and ArqA multiplexes still on low power. ArqA will go to its final location and power level on 23 November after Tacolneston finishes switchover on that date.
If you had reliable digital reception before switchover, you should already have a wideband aerial. I'd then suspect too much signal - see Freeview signals: too much of a good thing is bad for you | ukfree.tv - independent free digital TV advice for more information.
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Brian: Contact your landlord or management agent. The signal levels are expected to be sufficient for a very good chance of reliable reception at that postcode, which means that probably there's too much loss in the building's distribution cabling.
They will have to be prepared to recalibrate and possibly retune the system at switchover anyway, depending on how it's constructed.
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Briantist: You could use something like Gravatar instead: Gravatar - Globally Recognized Avatars . I admit my identicon is pretty boring, just a few purple triangles in the corners.
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Bruce Dorward: It could also simply be a fault at the Border news studio meaning that they couldn't actually put the programme out. If this happens ITV normally will find a different region. Having said that, the programme is online at
Full Programme Repeat | Border (ITV Lookaround) - ITV Local
.
If you were watching ITV1 +1 you would expect to get Granada, as ITV have only got enough time-delay equipment and monitoring for six services - the licence for your region is for 'ITV1 +1 Granada Border', and the content comes from Granada as that serves several million more people than Border does. They only have room for six time-shift services on satellite, which may explain the limitation on Freeview.
I believe Border is also low on the list of regions to get an HD upgrade, and you should expect to get Granada news on ITV1 HD (logical channel number 51) until the rollout is complete. It may also be up to the BBC to sort out enough versions of the HD multiplex to carry it.
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Rich: Many of the North Norfolk relays exist only to provide the 'correct' local news to viewers otherwise covered perfectly well by the Belmont main transmitter in Lincolnshire. If you provide a full postcode we can check whether this is possible.
The transmitter sites, masts and aerials are owned by Arqiva but they are simply contracted to transmit the six licensed multiplexes. The commercial multiplexes are SDN (owned by ITV plc) and ArqA and ArqB, owned by a different division of Arqiva. In turn they're operating on a commercial basis and would have to increase their prices a lot to cover the increased costs of transmission. It's expected to be about a 70% increase in costs to transmit from all relays, even if frequencies could be found, which they probably couldn't.
Digital UK know the answer to that question, as an organization, but I'd expect it wasn't in the call centre's script.
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tony: First, make sure you do a full retune - also called first-time installation, full reset, factory reset, virgin mode, default setting. It may be under the Software Update menu rather than under Installation or Tuning. Some boxes won't store channels that they think they already know about, you have to clear the existing channel list. You'll need to do this again on the 23rd.
Check whether your box is on the list of equipment that is known not to work with 8K mode - http://www.digitaluk.co.u…ment . If you haven't retuned for a long time it could also have a problem with a larger Network Information Table - see http://www.digitaluk.co.u…tnit .
There are also some boxes which have a bug meaning they can't pick up transmissions in 8K mode when there is a negative frequency offset. The box will say 'T810' on its sticker somewhere. See Unofficial Vestel PVR Information (UK) - T810 Freeview Recorder and Unofficial Vestel PVR Information (UK) - Digital Switchover for more information on those.
Assuming you didn't have any trouble with BBC Two analogue before switchover, it's unlikely to be single-frequency interference. It could be that the total signal level received is now too large, though, now that the new Great Yarmouth transmitter has started up.
If the BBC channels are stored - after doing the full reset - but are too weak to actually use, your box may have tuned into Great Yarmouth rather than Tacolneston. There may be a working set up at 800 or so in the channel list. In that case, see Digital Region Overlap for thoughts on how to sort this out.
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Bill: Yes, the Ravenstonedale transmitter is 'Freeview Light', it only carries the three public service multiplexes, so you wouldn't expect to get Dave or Yesterday.
The predictor shows a poor chance of getting reliable reception of the commercial muxes from Caldbeck. The PSB muxes offer a good chance of reliable reception. You could try it, but you might need to have a particularly large aerial installation.
If you do this, Digital UK show that your reception of the commercial multiplexes from Caldbeck will get worse after the Bilsdale transmitter switches over next September, for about a month before Divis (Northern Ireland) switches over. Once that's done, Caldbeck's commercial muxes can go up to their full output power, restoring roughly the same (still poor) prediction.
It may be easier to go with satellite, although Dave and Yesterday are both Sky-exclusive subscription channels at present.
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gordon: No further power increases are planned. The COM multiplexes are intended to be half the power of the PSBs - they are not required to equal the PSB coverage.
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Alex: This TV is on Digital UK's list of equipment that has a problem with the larger Network Information Table - http://www.digitaluk.co.u…tnit . That document provides a phone number to contact Sony.
Other posts on forums suggest that you should be doing a retune by pressing a '?' button, which may be on the TV itself.
There is a manual retune guide at http://www.digitaluk.co.u….pdf .
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billy: The overall multiplex bitrate of BBC A is higher than Mux 1 was, but the BBC are required to clear Mux B for HD. They have to cram the services from Mux B - BBC Four/CBeebies, BBC Parliament, and the national radio stations - onto BBC A as well as those that were previously on Mux 1.
For the next two weeks, those services are still carried on Mux B as well as their new home on BBC A, so may appear twice in your channel list.
Overall, the bitrates for each service are expected to be about the same as before switchover, or a little less. CBeebies/BBC Four usually runs about 4 Mbit/s, BBC Parliament about 1.5 Mbit/s, and the radio stations something like 1.5 Mbit/s.
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lm: I'd still argue that it's a communal facility provided for the tenants by the building management, and some part of your rent or building management fees should be going towards its upkeep. See PARAS - Professional Aerial Riggers Against The Sharks for thoughts on who to speak to and what to say.
You certainly shouldn't expect to pay for this yourself.
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Alex: As I understand it, manufacturers can put their updates into a queue managed by the Digital TV Group's Testing group - Book an over-air download | DTG Testing .
I would expect the protocol to be DVB-SSU - DVB standards can be found at DVB - Digital Video Broadcasting - Standards & BlueBooks .
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Clive Windy: Transmissions can travel a very long way, sometimes - under particular weather conditions - far further than planned. You can still get enough signal to detect even if it's not usable. I suspect the transmission on C52 is Emley Moor near Huddersfield.
Your mother's box must be one of those that simply stores the first version found rather than the best quality or strongest. See Digital Region Overlap for ideas on how to handle this.
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Matt: The prediction for Mux 1 at your postcode is variable - only 4% of locations within your grid square are predicted to get reliable reception. This may be because the Heathfield transmitter uses C34 for Mux 1, although that is fairly low power. Crystal Palace also uses C34 for Mux C, at the same power level as Rowridge.
It's shown as 'variable' rather than 'poor' as there's a very good chance of getting reception 50% of the time. It will depend on weather conditions whether it works at any given time.
Switchover at Rowridge starts on 7 March 2012. Until then, there really isn't anything much you can do. A slight adjustment in the aerial's position, moving it slightly clockwise or anti-clockwise, might change the level of interference. It might have been aimed a bit north of Rowridge to improve reception of analogue Channel 5 from Fawley (which was turned off two years ago to facilitate Rowridge's retune, in turn to free up channels for the south west region's switchover).
The commercial multiplexes will remain on low power on their current channels from 21 March to 18 April 2012, as the final channel allocations clash with low-power services at Crystal Palace until that date. You will need to retune again on 18 April. If, after the retune, you find that the commercial multiplexes are unreliable, it may be worth re-orienting the aerial for vertical polarization.
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billy: The symptoms you see are indeed the same as too little signal. The distorted signal pulls the 'value' of each carrier away from the value it should have, so it's interpreted incorrectly. Some carriers will not be disturbed enough to be misinterpreted, so error correction may be able to determine what most of the missing bits are, and reconstruct a block for the video and audio decoders to display it or play it back. Break-up happens when a block is detected to be uncorrectable or if the decoder runs out of valid data to play back (data is buffered, stored temporarily in memory; problems occur when the buffer runs empty). If the error rate is too severe, then the data which tells the receiver what channels are contained in this multiplex can't be decoded, and the receiver won't store it. In the most severe cases, the special Transmission Parameter Signalling carriers - which use a very robust scheme, transmitted redundantly, to indicate how the rest of the carriers are encoded - can't be decoded and the box won't even know the transmission is there.
There's really no way to tell whether it's too much signal without just trying to reduce the level and see what happens. Try disconnecting the aerial cable. If it works, you have grossly too much signal. If not, try an unamplified indoor aerial. Again, if it starts to work, too much signal. If you have a booster, take that out and see what happens. Amplified splitter in the loft or masthead amp? Bypass it, check the result on one TV.
Even if you have a signal strength meter, it may not be reliable. Each box seems to be calibrated differently. I strongly suspect that some have been calibrated to maximum possible input on one channel, but the distortion is caused by the SUM of all signals being too high, so you have to stay substantially below the maximum limit for 'safe' operation. I've seen reports that some boxes will report low signal levels when the levels are in fact high - my assumption there being that the box responds to not being able to decode by turning up the automatic gain control, and it's actually reporting the gain control level as the signal strength.
I usually look at Digital UK's postcode checker and make a guess. If they're shown as being within a short distance of a main transmitter and/or the prediction is 99-100% across the board, I usually assume too much signal :)
There are actually very few places in the country where you can have too little signal. Generally the problem is too much interference - the frequencies are very heavily reused across the country. It doesn't matter how much you amplify the signal, you amplify the interference just as much, and you add some extra noise from the amplifier itself. Amplification is only useful to offset losses along a cable, or occasionally if you have a very noisy receiver - see Usage and abusage of DTT TV booster amplifiers for how to use boosters correctly.
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lisa: It's very hard to say that you're 'on' Sudbury or Rouncefall, both have quite a large area of influence and the overlap area is large. If you do get ArqB on C50 now - the channels that Dave listed - you will lose them on Wednesday and will have to retune to get them back. If you don't get them now, you *might* get them by retuning on Wednesday. However, it remains on lower power, so you're still not predicted to get them (if you're still at the address you were before).
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lisa: As for *why* it's moving frequency: it's to give up C50 for Tacolneston to use from next week. The planned final home for this multiplex is C56, but this can't be used yet because Dover is still using it. There is another retune on 27 June 2012, the same day as stage 2 of Dover's switchover, when Sudbury's commercial multiplexes will all move to their final channels and power levels.
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Monty: At that postcode, the predicted coverage of the ArqA multiplex (which carries Challenge) from Belmont is good, though not quite as good as the others.
It's worth checking that your box hasn't tuned in Emley Moor on UHF channel 52 instead. This is expected to be significantly weaker. Some boxes just store the first version of a multiplex that they find. See Digital Region Overlap for ideas on how to resolve this.
If you didn't have digital before switchover, you might still have a Group A aerial, which won't pick up C53 or C60 very well at all. A wideband aerial is recommended. If the cable installation is old, it could be letting in water which increases the losses much more at higher frequencies than lower ones.
The ArqA and ArqB multiplexes from Belmont are still on low power for another week, until Tacolneston (which currently uses these two channels) completes its switchover. The problem could just correct itself next Wednesday - although given that prediction, I would have expected very occasional breakup, not complete loss of channels.
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John Plant: Derby only provides the three PSB multiplexes. Its purpose originally was to provide the East Midlands BBC One and ITV1 services to viewers using the Sutton Coldfield transmitter.
C48 is Derby BBC A and C46 is Sutton Coldfield D3&4. C29 is Waltham SDN. That suggests your box/TV just stores the first version of the channels that it finds.
The predictions are slightly better from Waltham than from Derby, so I suggest you do a manual retune using the channel numbers on the Waltham transmitter page. See Digital Region Overlap for more ideas on how to get the services you want tuned in.
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There is also a retune at Sudbury on Wednesday morning, with ArqB moving from C50 to C63. This releases C50 for Tacolneston ArqB next Wednesday, C63 having formerly been Tacolneston Mux 1.
Sudbury is still blocked from going to final channels until Dover completes switchover in June.
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Dave Caunt: I don't think anything has particularly changed. This week I can't get Mux C (C34) where frequently I'd be able to, but I'm having no more problems than usual with Mux A. I'm in Caversham, Reading.
A lot of tropospheric enhancement has been predicted over the last week: Tropospheric Ducting Forecast for VHF & UHF Radio & TV . This weather condition allows signals to bounce along between layers in the atmosphere without losing a lot of power. It could be interference from overseas stations, or possibly from Rowridge which also uses C32.
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Brian: The SDN/Mux A multiplex remains on C31 until 9 May 2012.
C51 is the final location but it is currently in use at Hemel Hempstead and can't be used until after the London switchover is completed on 18 April. I'm not sure what the reason for the three-week delay is. Possibly the programme of Olympic test events between 18 April and 8 May (the broadcasters are likely to need a degree of stability to test their equipment before the Olympics proper start at the end of July).
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Tim C: The BBC cares about when they shut down. The commercial channels don't. I'd bet on 01:30 for BBC One to shut down; the commercial channels will probably already be off - though they might still go off at, or shortly after, a programme junction, as they did for Crystal Palace's power tests.
Usually it takes a while for things to be reconfigured for the new transmissions, but at Tacolneston, the new services will be on the new mast, so everything will already be set up.
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Sandra Wright: If you stop subscribing to Sky, you can still watch the free-to-air and 'soft-encrypted' channels - see Compare Freesat and Freesat-from-Sky TV | ukfree.tv - independent free digital TV advice for the list of services on 'Freesat-from-Sky'.
However, Sky will disable the recording and time-shifting features of the box, and you won't be able to watch anything you previously recorded. It's possible to transfer recordings of free-to-air channels to a PC using a tool called +Extract - +Extract - free software that rips free-to-air recordings from a Sky+ hard disk .
These are software limitations but I'm not aware that anyone has taken the trouble to write new software for the boxes that would remove these limits. As far as we know, the only way to get recording without paying Sky any money is to buy a different box.
Generic free-to-air recorders are also available, but Freesat-branded boxes will have a full Electronic Programme Guide, series link, accurate recording, etc - all the features you're used to from Sky+.
The link above does show a relatively small number of channels that are in Sky's service but not in Freesat's. Note that 5* and 5 USA, and their +1 time-shifts, will be joining Freesat on 8 December, according to Generic FAQ F to J | Channel 5 . Pick TV and Sky News are unlikely to ever come to Freesat as they are Sky-owned channels.
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Ian: I'm afraid it's not very likely. It's expected to roughly double the cost of transmission to broadcast from all relays, which would only increase the overall coverage by 8% of the population. There also aren't that many spare frequencies, although Scotland is better off than elsewhere as you're not that close to other countries! If the broadcasters do extend coverage it's most likely to be at transmitters that cover a large number of households with low power, and that are easy to feed. Penicuik is predicted to cover 9,900 households, joint 50th (of approximately 1000 'Freeview Light' relays not carrying all muxes).
If you provide a full postcode, we can see whether another transmitter is likely to give reliable results; however, I wouldn't hold out a lot of hope, as Penicuik is quite a distance from the edge of the old analogue coverage areas of Craigkelly, Black Hill and Angus (which does have some overspill into Midlothian, around Dalkeith, but not as far south-west as Penicuik).
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James Lowther, John: UKTV, which runs Yesterday, say:
"Are you planning on putting any UKTV channels on Freesat?
Dave, Really and Yesterday are available "free-to-air" through Freeview only at present, and we currently have no plans to launch any channels on Freesat."
You can send them a message at Contact us .
There are suggestions that Sky may be subsidising their carriage on satellite, though I note that all of UKTV's standard-definition channels are on two transponders, which don't carry channels from anyone else, so they could be leasing the transponders directly. It's likely that, like Channel 5, they would have to lease new transponders on the 2D or 1N satellites, with a UK-only footprint, before they could move to Freesat.
The HD variants are sharing transponders with channels from other providers.
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Robert Lee: Briantist is definitely talking about Bangor in Wales, which is near the transmitter at Llanddona (on Anglesey), while Jordy is talking about Bangor, Northern Ireland, for which no spare frequency is available.
Briantist's assumption must be correct as Ofcom's list of sites is based on main transmitters - carrying all six multiplexes - only.
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Adrian, Ian: The detailed study on which sites are viable, and why, is at xhttp://www.ofcom.org.uk/static/tvops/ArqivaReport.pdf . Basically, there's no channel available to serve Derby.
"Spectrum in central England is limited and available channels are restricted."
Just squeezing in the Derby relay was difficult enough, with the digital services initially starting up at Waltham DSO 2 on former analogue channels and only moving to final channels after Sutton Coldfield DSO.
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Arqiva's Reference Offers for Transmission Services and Network Access have now been published at Useful documentation .
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Ian: You can only make a red button service available where there's capacity to run the stream! The red button really only saves getting a Logical Channel Number from DMOL for the service (and BBC Red Button interactive stream actually has one - it's on 301). I don't think DMOL even charge for this. On the other hand, the MHEG program to handle the red button and switch to the alternate video stream would have to be carried by whatever the entry point service was - so you're basically asking the Nottingham service to advertise its competitor!
Local TV has to be carried on a new multiplex from somewhere, or Ofcom have to force a PSB multiplex to free up several slots to carry enough regional services from each transmitter. The PSB multiplexes are already full up, except a small chunk of D3&4 that ITV plc are likely to reclaim, once the squatting Rabbits are kicked off and the capacity is big enough to run a full channel. The COM muxes are not set up to run different regional content (except SDN in Wales).
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Ian: A red button service takes exactly the same amount of space as a regular channel. Possibly slightly more. The vast majority of the space required is the video stream, running at 1.5 - 2 Mbps, and I'm assuming it has to be running the whole time.
Now, you could perhaps suggest that a Derby service should be carried on the same multiplex as a Nottingham service. No argument with that - except that a service from Waltham is not allowed to point towards Derby because the allocated channel clashes with The Wrekin to the west. The Wrekin's coverage area goes as far north as Tarporley and the west side of the Birkenhead peninsula (though I'd expect viewers there to be using Winter Hill even if it doesn't give the best results), which means the axis on which Derby lies, relative to Waltham, is not possible.
This restriction actually means that the Nottingham service won't serve the west side of that city particularly well.
The alternative is a service from Sutton Coldfield, but the channel allocated there - 51 - is already in use at the Littleover relay and therefore cannot be aimed to the north-east at all (it's also used at Emley Moor for the SDN multiplex).
Again, the government is not going to propose stealing capacity from the COM multiplexes. Ofcom are allowed to allocate capacity for PSB services on up to two multiplexes, which they have used to designate capacity for S4C (in Wales) and Channel 5 on the D3&4 multiplex, and for ITV1 HD and Channel 4 HD on BBC B. But you'd have to require the operator - let's assume D3&4 - to free up a slot for each community you wanted to serve, within the whole BBC/ITV sub-region, kicking off far more services than I think you'd want to.
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Des Collier, Ian Grice: Channel 5 were the only applicants. Unless there was some kind of gentlemen's agreement that ITV (or other Channel 3 licensees) and Channel 4 would not bid this time, you have to assume there isn't that much interest at this time.
ITV plc did announce plans to acquire Channel Television at about the same time, perhaps indicating a problem getting agreement among all ITV licensees. The Order directing Ofcom to run these auctions requires any bid from "Channel 3" to represent at least 13 regional licencees. With the acquisition of Channel TV, which completed on 24 November, ITV plc now own 12 plus the national breakfast licence.
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aron: The commercial broadcasters are only required to provide at least as much coverage as they did before switchover started. They have decided not to extend their services to any further transmitters at this stage.
High Wycombe is joint-31st in terms of household coverage, of transmitters that do not carry the commercial multiplexes. There are five transmitters that do, which are predicted to serve fewer households, but - with the exception of Saddleworth - they are all in the Scottish Islands and were considered 'main' transmitters in the analogue network. The coverage statistics are for 'preferred' transmitters, a service from a main transmitter may still be possible.
Most households in High Wycombe are probably covered by the main transmitter at Crystal Palace. This will be getting a significant power boost to increase the digital coverage area to the same as the analogue one, or even a bit larger. Receivers can be desensitised with loud transmissions on adjacent channels, but High Wycombe's broadcasts are right up at the other end of the spectrum from Crystal Palace's.
There are also 'Freeview Lite' relays at West Wycombe, Chepping Wycombe and Micklefield, indicating that this may be a difficult area for reception from Crystal Palace.
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Chris B: The Hannington transmitter has restricted digital coverage to the east. A whole area from Wokingham down to Basingstoke is effectively not covered, or only covered poorly. This is because Hannington uses the same frequencies for digital services as Guildford does for analogue services, and the analogue services had priority when digital was introduced. Digital UK's postcode checker suggests that you are affected, though less severely than if you were further south.
This restriction will start to be lifted from switchover, matching current analogue coverage: 8 February for the BBC channels, 22 February for ITV1, ITV1+1, ITV2, Channel 4, C4+1, E4, More4 and Channel 5. The remaining channels have to remain restricted until Guildford completes switchover on 18 April 2012.
You must retune on both 8 and 22 February as services move to different frequencies - taking over some of the old analogue frequencies. You may need to retune on 18 April if some services aren't picked up.
Loft aerials are unlikely to become damaged due to weather, unless of course your roof leaks! Also, you still might have trouble if the cable runs outside, particularly if there are any junction boxes. However, signal strength is reduced when passing through the roof or walls, and there's a greater chance of signals from elsewhere being picked up, due to reflections off other surfaces.
A wideband is not necessary for reception from Hannington - all transmissions before and after switchover are in the analogue group, Group E. Future changes might change this, but no changes are expected for at least two years.
There is a deliberate moratorium on works over the Christmas period. Engineering generally is carried out from February to November, the weather isn't suitable for any mast works in winter. No faults have been reported. Signal propogation - how well the signal travels from the transmitter to your aerial - does vary with weather conditions, and these can either increase or reduce signal strength or interference, and can do so differently on different frequencies.
As you have recently retuned, your TV may have decided to tune in another transmitter, such as Crystal Palace, rather than Hannington. If so, see Digital Regional Overlap for thoughts on how to fix this.
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Dave Lindsay: Anything reported via the BBC - with [BBC] at the end - is a fault, not planned engineering works.
The BBC only report faults on their own channels: BBC One and BBC Two analogue, and Mux 1 (BBC One/Two/Three) and B (BBC Four/CBeebies, BBC Parliament). Faults on ITV/C4 etc are not recorded.
The high winds today would mean any planned engineering works would probably have had to be suspended anyway. There weren't any planned for this week (see
Digital UK - Planned Engineering Works for updates).
James: A total absence of anything usually indicates your aerial has fallen down or been damaged, or that a cable has become disconnected. If you're using an amplifier, check that the power supply is plugged in and switched on and that the fuse hasn't blown.
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colin: I suspect you've only just discovered information that has been known all along; that the commercial multiplexes have to run on lower power until 27 June 2012, because of a clash with Dover. Basically, increasing the power at Sudbury any earlier would cut off services for many viewers of the low-power digital services, and even cause problems for some analogue services. Once Dover has switched over - on 27 June - the restrictions at Sudbury can be lifted, and final channels and power levels can be used. You will need to retune on this date.
Compared to pre-switchover reception, the current coverage might be worse as although the power levels were increased somewhat, the transmission mode was changed, trading off increased capacity for reduced coverage, and the increased power level doesn't quite make up for the mode change. The mode was changed again on 22 November, again to increase capacity, which may have reduced coverage a bit, as there was no power increase to compensate this time.
The mode changes were purely commercial decisions by Arqiva, who had pre-sold the additional capacity on ArqB before Sudbury switched over. The extra capacity was sold to BT to carry Sky Sports 1 and 2. The BBC had agreed to match this extra capacity with their own unused space on Mux B before switchover, so if the ArqB mode had not changed, all viewers paying BT or Top-Up TV for Sky Sports would have lost the channel. (This happened at Mendip, for example.)
This information has all been in Digital UK installer documents (except the detailed information about interim power levels). The brochures sent out have perhaps been too simplified, over-emphasising the idea of two stages and everything's done, when at many sites - and particularly the Anglia region - more stages are required. The Anglia booklet does include additional retune dates in 2011; I think the exact date of Dover's switchover wasn't announced when it was published, so 2012 dates weren't included. Some indication should have been made of further retunes being required in 2012.
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Fawley closed on 25 March 2009. It had to give up C34 so that Rowridge could use it, to free up some channels for Stockland Hill PSBs.
The one-channel relays at North Winchester, Hythe (Hants) and Hatch Bottom - which were built to transmit the 'correct' ITV1 subregion to a few areas when Meridian introduced the 'north' service from Hannington - will presumably close when Rowridge closes, although they are already essentially redundant as ITV plc have closed the 'north' service, and will be redundant from 22 February as all other services will be digital, from Hannington. It depends whether there are any frequency clashes with transmitters in the Hannington or Midhurst groups. Midhurst itself will use C59 for ArqA, which is currently used by Hythe (Hants), but it could be restricted to 5 kW until after DSO 1 in the Meridian East region (20 June 2012).
KMJ,Derby: Yes, this information is in Ofcom's 'Table of Digital Stations' at Ofcom | Supplementary licence documents in relation to DSO . Woodbridge Mux B is temporarily on C57 until 27 June 2012. Wivenhoe Park D3&4 is also on C64, not C51 as had previously been advised.
It looks like Ofcom are not going to update the 'DSO Details' information any more. They should really replace it with a pointer to the correct information in the Licensing section.
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NottsUK: Probably for the imminent BBC One HD Scotland, Wales, and Northern Ireland services, then.
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Hannah: If the TV doesn't have a digital tuner built in, you will need a new set-top box before switchover happens in April. If you could previously get ITV2, BBC Three or similar on the TV itself, more than just BBC One, Two, ITV1, C4 and C5, it has a digital tuner.
Only getting Channel 5 is unusual. Have you retuned your TV's analogue tuner since moving? Some apartment blocks with a distribution system - often called a Master Antenna TV system - use transposers to reduce ghosting problems which occur when the direct signal from the transmitter is pretty strong, but not strong enough to use directly. The transposer puts the signal from the wall socket on a different frequency from the one broadcast from the transmitter. That might mean that your TV would need to be tuned to different frequencies than the ones listed at the Crystal Palace web page.
It's also possible that you were using a relay transmitter before; in this case, again you would need to retune the TV's analogue tuner.
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John Andrews: As long as you can connect the box to the TV, you can watch.
The SCART connector is probably the easiest way to connect. While broadcast transmission standards were a little different, the way that pictures are sent on a cable is the same in both countries. You may need to check that both the box and TV are set to RGB or to CVBS mode - this setting controls whether colour is sent on three separate wires, one for each colour, or all combined onto one wire.
If the box and TV support a digital connection like HDMI, that's an even better solution.
You might not be able to use an RF connection, even if the box has an RF modulator that supports it. Portugal used PAL colour with 625-line System B/G for analogue transmissions, while we use PAL with System I. The sub-carrier frequency used for audio is a little different, so you may well get pictures but no sound. Newer TVs usually allow you to select the system used, so you might be able to select PAL I rather than PAL B/G on the TV. But if it's that new, it should have SCART sockets!
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Trustix22: The core standards used for digital TV are the same in France and in Britain - DVB-T with pictures encoded in MPEG-2 Video and sound in MPEG Layer II - so it's not surprising that it mostly works. However, France's system is fully specified in IEC 62216 (sometimes called the Euro-Book or E-Book) while ours is in the Digital TV Group's D-Book. Some of the service information is not fully compatible, so you might find that PVR series link and the like doesn't work.
Notably, for interactive services, I believe France use the Multimedia Home Platform (MHP), which is based on Java, while UK Red Button services use the MHEG-5 program description language and the 'UK Profile' object model. That means BBC Red Button and other interactive services won't work on a TNT box.
I also believe France still uses essentially standard teletext, which is carried differently for digital TV, but the content format is the same. UK transmitters, including the Channel Islands, do not broadcast standard teletext data, only the MHEG-5 content.
Subtitles should always be available as I believe both UK and Europe use the DVB Subtitles standard, which carries the subtitles as a picture overlay. Make sure you use the subtitles button on the box's remote, rather than trying to access teletext from the TV.
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MAGGIE: A couple of additional differences:
After cancelling, the Sky box will show all channels in the guide that you *could* get if you re-subscribed, not just the ones you can get without subscribing. A Freesat box only lists the free-to-air channels. That might make it simpler to use.
This site has a page to compare between channels available through Freesat and through Sky's free service: Compare Freesat and Freesat-from-Sky TV | ukfree.tv - independent free digital TV advice .
If you have Sky+, you should be aware that the pause, time-shift and recording features will be disabled when you stop subscribing. You also won't be able to play back anything previously recorded. I believe you can still pay a reduced rate of £10 per month to keep these features but you have to ask for it. If you still want these features, you'll have to get a Freesat+ recorder.
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Rowridge, Sandy Heath, Sudbury, Heathfield and Tunbridge Wells changes are all just moves from temporary channel allocations to their final allocated channels - they're not part of this DTT Clearance Retrofit programme.
Heathfield and Tunbridge Wells retunes (and power-ups and mode changes) are only two weeks after their DSO 2 dates; Bluebell Hill needs C42 until its own DSO 2 date on the 27th.
Rowridge can't use the allocated 22/25/28 until Crystal Palace DSO 2 as these are used by Mux 2, 1 and B at present. CP will still use these channels for the COM muxes but at 10x current power, offsetting the increased interference from Rowridge.
Sudbury's final channels are currently used at Dover for two low-power muxes and one analogue channel, so Sudbury can't adopt them until Dover completes switchover.
Sandy Heath has to wait for Hemel Hempstead to give up C51 - currently BBC One analogue at Hemel.
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Janet Pope: Unfortunately these channels are carried within the same groups of channels - multiplexes - as channels you probably do want. There are some on each of the commercial multiplexes.
You can delete them from the channel list if your box or TV provides that feature. If not, you can create a Favourites list on many boxes or TVs, and only include the channels you want to access on that list.
If you want to make sure, boxes should have 'parental control' features. On my Humax PVR-9200T, you can select an age limit, and any programmes transmitted with an age limit higher than that require you to enter a PIN to watch them. It does require the broadcaster to label the programmes correctly - I've never used the feature so I don't know how accurate they are. Check the TV or box's manual to find out how to enable parental control.
If you delete channels or set up a favourites list, check the manual to find out how to ensure that only you can reset or retune the TV/box, or how to lock it to only show that favourites list.
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Trevor Lord: Digital UK's predictor gives a poor prediction from the only option available to you, the Selkirk mast. This means that for you, variable reception is expected a lot of the time. I would expect that the analogue picture quality before switchover was poor.
You would probably be better off getting satellite or cable. You can get satellite TV without a subscription through Freesat, paying a one-off cost for the box and the dish installation. Or you can get a free service from Sky, which has a slightly larger range of channels, but you can't have PVR functions without taking a subscription - the box will also list all the subscription channels in the programme guide, so it can be hard to find what you want to watch. You also have to pay up-front for 'Freesat-from-Sky'. To compare the available channels, go to Compare Freeview and Freesat TV | ukfree.tv - independent free digital TV advice .
If you take out a Sky subscription, the box is free. However, a year's basic subscription at £20 per month would pay for a very good Freesat box, with a substantial amount left over!
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Tracy Gill: Check if you have another version of the BBC channels anywhere else in the channel list (usually from 800 upwards). If they do appear, the problem is that your box is tuning in the weaker signal from Stockland Hill rather than the strong one from Mendip.
Unfortunately a lot of equipment designed before switchover started simply stores the first channels it finds. That was fine when power was low and most people would only expect to have strong enough signals from one transmitter. After switchover, many - perhaps most - people will have strong enough signals from more than one transmitter, at least strong enough to decode and store the channel list even if not strong enough to actually use.
See Digital Region Overlap for thoughts on resolving this. Newer equipment should ask which region you want, if more than one is received, and use the best available transmitter for the selected region(s).
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David: Yes, Google do follow what you do. That includes tracking which websites they have served adverts to you, so they can serve more ads that they think will be relevant to you on other sites, not just what you search for. If you want to opt out, go to Advertising and Privacy Google Privacy Center .
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ann legg: It sounds like the aerial cable split is at the back of the main set. You will get much better results by splitting the cable as close to the aerial as possible. You might then need to add a small amount of amplification before the split, to offset the loss caused by splitting and the length of the cables.
Putting a booster at the back of the set with the problem will almost never improve things - only if the set itself is particularly noisy.
I'm surprised that changing channel and back makes an improvement.
If the split is at the back of the second set - that is, the combined length of cable from aerial to main set is longer than the length from aerial to second set - then you probably have too much signal.
Do check - by comparing the frequencies - that both TVs are tuned into the transmitter that the aerial points to. Digital UK predict usable signals, at least on the public-service multiplexes, from Carmel, Wenvoe, Kilvey Hill and Preseli. If the set with the problem is older, it may simply store the first version of the channels that is found, when scanning from lowest to highest channel numbers. Signals can still be strong enough to be stored even if the aerial is pointing in a different direction. For you, Kilvey Hill would be found first, then Wenvoe, then Preseli, and finally Carmel.
Digital UK list Carmel as your best option as it should give overall best results, but Preseli has (very slightly) the best results for the PSBs. The commercial multiplexes from Wenvoe and Preseli use the same frequencies so effectively cancel each other out - a variable service is predicted from Preseli but very poor from Wenvoe.
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Dave Lindsay, Mark H: While the COM muxes at Stockland Hill will increase to final power in April, the prediction for Mark H actually goes down slightly. This is because Rowridge will be using the same frequencies at high power, from the same date. They are actually going to be using the same frequencies for the same services, but the transmitters are too far apart to use Single Frequency Network techniques, so they will just interfere with each other. (Crystal Palace will also be a problem, to a lesser extent.)
The likelihood is that for a number of people in your postcode, the COM multiplexes will be unreliable for some of the time. Careful siting of the aerial may find a reliable location - it's best to get an experienced installer to do this.
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David Brackpool: Is your aerial pointing to Whitehawk Hill or Rowridge?
If Whitehawk Hill, the aerial would be oriented with the elements running up-and-down, and pointing south-east. If Rowridge, the elements would go side-to-side and it would point south-west.
If the aerial is pointing to Whitehawk Hill, you should check that the box is actually tuning in that transmitter. The behaviour on many older boxes is just to store the first version found, when scanning from lowest to highest frequencies. Rowridge's frequencies are all lower than Whitehawk Hill's.
For Rowridge, the prediction is for variable coverage of Mux 2. This will be better after switchover but the commercial multiplexes are still predicted to be variable, even if you switched the aerial to vertical polarization after all services start up on VP on 18 April.
The prediction for Mux 2 from Whitehawk Hill, currently, is lower than for the other multiplexes, but still over 95% of locations in the 100 metre x 100 metre square that your postcode is centred on are predicted to have reliable reception for 99% of the time.
Recent weather conditions have been predicted to cause distant signals to come in stronger than usual, which might explain the problem. If you retuned when this was happening, it could have caused a distant station to be stored that now can't be picked up - in which case, retune again. You can find maps of predicted 'ducting' weather conditions at Tropospheric Ducting Forecast for VHF & UHF Radio & TV .
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Tim McEwan: I'm afraid I can't find a detailed spec or manual for that TV online.
For Freeview HD, the TV has to support the newer DVB-T2 standard and the BBC's method of encoding the programme guide (this is a very rudimentary copy-protection measure). Equipment that supports both should have a Freeview HD logo on the packaging somewhere. You could check to see whether the manual mentions DVB-T2. If it only mentions DVB-T, I'm afraid you'll need an additional Freeview HD box.
If the TV definitely supports Freeview HD, not just 'HD Ready', the most likely answer is Short Reflector Syndrome: http://www.wrightsaerials….pdf .
Wideband aerials aren't very good at the lowest frequencies, but you don't have much choice with Sandy Heath as the commercial multiplexes are in the middle of the frequency range, and a Group A aerial won't receive them. The cut-off is very sharp for frequencies above the range that the aerial is designed to handle.
If you can get into a manual tuning screen for the TV, it may be possible to show the signal strength for C21 and compare it to the strength for C24 and C27. If they're similar, it's the TV, not the aerial.
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Jim: Yes, you really need a receiver that supports DiSEqC to switch between the different feeds. You can get manual switches but it's likely that different satellite clusters will use the same frequencies for different channels.
There are Freesat receivers that support DiSEqC - you would need to put it in non-Freesat mode to tune in the other satellites. There are also Free-To-Air receivers, not Freesat-branded, which will treat all satellite clusters equally, but won't show all the Freesat EPG data. Sky boxes do not support DiSEqC.
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Briantist: The BBC have not yet applied to renew BBC B, it runs out in 2014. The renewal, if they take it up, will run to 2026.
Mux 1/BBC A will be 'until the Royal Charter is renewed', the next renewal is in 2017. I agree that it's likely to be the last to be replaced.
I'm also not sure about 'only HD carried in DVB-T2', implying that SD services would be excluded. Perhaps you meant 'HD only carried in DVB-T2', meaning HD wouldn't appear on a DVB-T multiplex, but SD could be carried on DVB-T2.
Charles Stuart: I would expect that if SD *was* carried on DVB-T2, it would be encoded with MPEG-4 AVC (aka H.264, MPEG-4 Part 10, ISO/IEC 14496-10) as HD is. That could reduce the data rate required substantially, compared to MPEG-2 Video as used for current SD services, but it all depends on content and the abilities of the decoder.
Currently the number of video streams per mux varies from seven (BBC A) to 11 (SDN) in approximately 24 Mbps. If layers 7 and 8 were deployed with the suggested mode capacity of 38 Mbps you could get 11 to 17 MPEG-2 SD video streams; with additional efficiency of AVC you might get 20 to 30. Layer 9 is expected to provide 35.8 Mbps providing 10-16 SD MPEG-2 streams.
HD has five times as many pixels as SD (comparing 1920x1080 to 720x576), the BBC usually run at 1440x1080 which is 3.75x. HD bitrate for video averages 8 Mbps - but the BBC think they can squash to 6-7 Mbps, allowing one more service - compared to about 3 for BBC One SD. So we should perhaps expect AVC to deliver similar results with around 40-50% of the bit rate of MPEG-2, for the same number of pixels.
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Ian Matthews: You might have your TV in the wrong mode. It should be set to PAL I for the UK.
Different countries used different frequency offsets for different components of the analogue signal. Most of Western Europe used System G on UHF, which - compared to the UK and Ireland's System I - uses the same method of encoding the brightness and colour information, and the same frequencies, but a different method of encoding sound and a different frequency.
Stereo sound was a later add-on, and some countries in Europe did use the same NICAM system as us, but again, on a different frequency.
SCART cables carry the sound on separate wires, so the connection from your Freeview box - if it is separate, not built-in - would not be affected. It would only be affected if your TV didn't have a SCART input and you had to watch the output of the box by tuning in a spare channel preset.
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Briantist: Agreed, there has to be a substantial amount of voluntary take-up - just like the switch to digital - before there can be any mandatory switch-off plan. To get voluntary take-up there has to be a compelling reason to do so.
However, many surveys have indicated that people are more interested in greater choice than in better picture quality. There are some people vocally against reductions in quality to cram in more channels, but the majority would seem to prefer more choice. Perhaps a bit more of both is what's needed.
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Briantist: All these changes (including the Meridian, London and NI changes) are already in the table incorporated into the licences, available at Ofcom | Supplementary licence documents in relation to DSO ('Digital Terrestrial Broadcasting Stations for Multiplex Licences' or 'Table of Digital Stations')
I'm actually surprised they've provided new documents in the 'DSO Details' section for the three regions yet to switch. I'd assumed that they wouldn't be updated further, given that there were three updates to the licences table at the end of last year without corresponding updates to 'DSO Details'.
There are a few notes in the 'DSO Details' documents not in 'Table of Digital Stations', in particular places where BBC A will start up on one frequency and then change to another at stage 2.
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Dave Lindsay, Briantist, Pat Hughes: The tender documents at RT: NI Project specifically say "integrated into Freeview *HD*". To me that implies DVB-T2, although it isn't specifically stated.
I know Brian's belief is that DVB-T2 muxes will carry HD only, but I think that's a promotional issue to drive voluntary take-up of T2 equipment - the value proposition of a greater number of new SD services is considered lower than the value of fewer additional HD services. I'd argue caution on that point, several surveys have indicated viewers are more interested in more choice than in better quality for the choices they already have. (You only have to look at the behaviour of the commercial muxes, continually squashing in more channels!)
The documentation doesn't state anywhere what mode is proposed. Without that information we can't tell what the coverage will be. It does appear from Saorview's map that Claremont Carn will be permitted to broadcast a lot of power to the north, providing a lot of the coverage - the mini-mux is there to fill in where overspill from the Republic doesn't reach. It *is* expected that the mode is substantially more robust than any of the options used by the main six muxes, and therefore much more coverage will be obtained from the low power levels available.
BT Vision boxes may well be able to decode the overspill Saorview transmissions, which are MPEG-4 AVC (H.264) carried on DVB-T. But I don't think we should assume that the mini-mux will use the same mode - it's not carrying as many channels, for a start.
The tender process should now have reached the dialogue phase with any applicants that have been shortlisted, but I can't find any public notification of who they are, or any more documents. We may not find out any more details until the end of March, when the contract is due to be issued.
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john preece: Generally you would connect a DVD player to a TV using a SCART connector. If the TV doesn't have a SCART (or doesn't have one available) you may be able to connect using HDMI, if it's an HD TV and a recent DVD player. After that, check for a set of phono sockets marked 'video', 'audio L' and 'audio R'.
To watch a DVD, you then use the TV remote's 'source' or 'input' button to select the socket or sockets you connected it to. It should show a menu or cycle between the options - they're usually called AV 1, AV 2, etc, although some TVs now include the name of the connector.
If you don't have enough SCART sockets on the TV, you can get a SCART switch box that allows you to switch from one device to another.
Very few DVD players contain the RF modulator necessary to make the DVD player appear, to the TV, like an analogue TV station that you can tune in to. This is the worst quality option anyway. If really necessary, you can buy an external RF modulator that plugs into the DVD player's SCART socket.
If you also have a Freeview box, it may have a second SCART socket. If the TV doesn't have enough SCARTs, it may be possible to plug the DVD player into the Freeview box, set the TV to display the Freeview box, and then set the Freeview box to display the DVD player (again, look for a 'source' button on the remote).
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Peter: Yes, exactly 100 kW.
The coverage still will not be equivalent as the commercial muxes have chosen to use a less robust, but higher-capacity mode. They have started making this changeover already. In addition, the PSBs got the best channel allocations, the commercial muxes will be subject to greater interference from other transmitters.
Finally, Rouncefall's transmissions help to reinforce Sudbury's coverage in many areas, but it only transmits the PSB services. The COMs get no help from Rouncefall.
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doug: These things are unrelated.
Nearly all free-to-air channels transmitted from satellites are included in Sky's Electronic Programme Guide. There are a few channels that aren't listed, mainly because Sky's listing prices are extortionate, but also Sky have to support old boxes that have limited memory, so no new SD channel can launch unless an existing one closes.
Sky (both the paid and free services) and Freesat use the exact same transmissions from the same satellites. You just can't watch any subscription channels on a Freesat box, because they are encrypted, and you need the Sky box and card to decode them. There are a few channels that require the Sky box and card, but don't need an ongoing subscription - these are called 'free-to-view'.
To watch a channel that isn't in the EPG on a Sky box, you go to Other Channels (press Services on the remote) and enter the necessary parameters. You can find parameters at sites like Eurobird 1 & Astra 1N/2A/2B/2D at 28.2°E - LyngSat or Astra 1N / Astra 2A / Astra 2B / Astra 2D / Eurobird 1 (28.2°E) - All transmissions - frequencies - KingOfSat .
The RF output is to allow TVs (usually additional TVs) to display the channel that the Sky box is decoding. This is tuned in as if it were an *analogue* TV station. You can select the UHF channel that it uses, and the installer may have already selected something that isn't in use in your area, so we can't really tell you which channel to tune into. Put your postcode into the box at the top-right of this web page to find suggested channels to use. If the Sky box is on, not in standby, it should be found when you use the automatic tuning feature of the TV.
It's recommended that you avoid channels over 60, because they will be used for 4G mobile phone/broadband once digital switchover is completed. Channels between 31 and 38 are due to be released as well, they could end up being used for digital TV (Freeview) or for something else.
I'm not aware of any Freesat box that has an RF modulator built in. If you do want to distribute the output of a Freesat box, you can buy an RF modulator that plugs into a SCART socket.
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Dave Lindsay, saintee!: Digital UK's postcode checker (which seems to be the most reliable source of information much of the time) says Perth BBC A will move to C39 some time in 2013, presumably before Angus ArqB makes the move from C61 to C49 (also shown as 2013).
The STV North Ofcom DSO Details document hasn't been updated since 5 January 2011. I wouldn't rely on it. The red markings inidicated that they are *likely* to change, not that they would *definitely* change. For regions that switched over later, like Yorkshire, some channels that were marked in red did change, and some didn't - though it's not necessarily true that all such changes in those regions have already been made.
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chuck: The Humax boxes must be in standby to perform the automatic update check at the scheduled time.
You can go into the Updates menu and do a manual check for updates at any time that it's being broadcast. See Welcome to HUMAX [Global Website] for details. They are broadcast on the BBC's mux 1, so you have to be able to receive BBC One at the point that you check.
This update was released in July 2011 and has already been broadcast several times. You may already have it.
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Glanville Carleton: See Digital Region Overlap.
Many Freeview boxes simply tune in to the first version of the services that they find. Of the transmitters you could receive from, Belmont (Yorks/Lincs) uses the lowest frequencies and will be found first. You either have to get a new box that will ask which region you want, manually tune to the transmitter you want, or find a way to get the box to ignore the transmitter you don't want.
Since your best bet appears to be Sandy Heath, which is only a couple of channels away from the unwanted services from Belmont, you might try adding an attenuator when retuning, to bring down the signal levels below the point where the box can decode them. Then unplug the attenuator when you use it normally.
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chuck: Pretty much the same applies to the 9200T. Its update is running next weekend, but the current firmware is even older, dating from May 2010 - it has been repeated every few months.
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Janie: I believe the Sky box in the bedroom would drop down to 'free-to-view' mode. You wouldn't be able to watch subscription channels, but you'd be able to watch all the channels listed at Compare Freesat and Freesat-from-Sky TV | ukfree.tv - independent free digital TV advice . You'd no longer be able to pause or record programmes on the bedroom box, if it's a Sky+ box.
Or, you could just unplug the Sky box and plug the Freesat box in, in its place. You'd lose the few channels that are in Sky's free service but not on Freesat - again, see that link for the comparison.
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Maureen: To get BBC iPlayer content on your Freesat box, it needs a connection to the Internet. The best way of doing this is to connect an Ethernet cable from the box to your home router. Or, you may be able to use WiFi if the Freesat box has that built-in, or if the manufacturer sells a 'dongle' that adds WiFi capability to the box.
'Homeplug' is a brand name for data carried over the house's wiring, meaning you don't have to run another cable. The capacity depends on how good the house wiring is, and they can cause additional interference on DAB and FM radios.
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Briantist: Brougher Mountain may not be planned to broadcast COM9, but Divis certainly is! Looking at the template at the back of Arqiva's 600MHz Reference Offer for Layer 9, it doesn't seem that C36 is as heavily restricted in the direction of Brougher Mountain as it is to areas to the south-west and west-north-west.
http://www.arqiva.com/cor….pdf , page 121 has the template for Divis.
It looks like the practical antenna for C36 from Divis may well broadcast only to the north and east, though: it's specified as four tiers of two panels rather than the 8 tiers of four panels used for layers 7 and 8.
The question is, what other transmitters is that template protecting? Presumably it protects some radar stations in Ireland, as Ireland doesn't have any sites using C36 in the GE06 frequency plan. If Divis would cause too much interference (albeit at 100 kW) I would assume that Brougher Mountain would also be a problem.
Brougher Mountain is in the Layer 7 and 8 sets at 10 kW power, so I'd have to assume that 2 kW on C36 just isn't allowed. Other transmitters have been planned for reduced power on Layer 9 compared to Layer 8, for example Llanddona is listed at 20 kW for Layer 8 but only 3.2 kW for Layer 9. (Again, there's a huge bite out of the permitted template to the west.)
Happy to be corrected if you have a source.
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Mick Bull: It may be that the cable is relatively old and of the 'low-loss coax' type. This traditional type of cable isn't actually very low-loss, and it picks up a lot of interference.
It's now recommended that systems use 'satellite-grade' cable such as Webro WF100, which has a dense copper braid over copper foil screening. These are much less likely to pick up interference.
The aerial itself can help - an older cheap aerial typically wasn't matched to the cable properly. The signal on the cable is supposed to be 'unbalanced', but the aerial elements are balanced. If connected directly, the cable ('feeder') picks up interference. To convert from one to the other, the aerial should include a balun (balanced-to-unbalanced transformer). This can be a printed circuit or a few turns of wire, and is pretty cheap, but the cheapest aerials didn't include them. These aerials are often known as 'contract' types as they were usually bulk-bought for fitting on new housing estates, but some installers would also use them for individual jobs.
A balun, and a feeder pickup test, are now required to pass the CAI Benchmark test, so they are usually included in new aerials.
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sadekali: PARAS - Professional Aerial Riggers Against The Sharks has some thoughts on who to contact if a communal aerial or satellite system isn't working. The first person to ask, if you're not sure, is whoever you're paying rent to.
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Norman Ansell: Digital UK's trade view suggests that the percentage of locations covered within your national grid square will - after all changes are made across the country - go down from 94% to 92%, for 99% of the time. For 50% of the time, it actually increases from 97% to 98% of locations served.
The 'Good' threshold, for which the planners consider the square to be served, is 70% of locations for 99% of the time. So really, it's not that significant.
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ukbg: Bulgaria hasn't yet launched digital terrestrial TV - the European Commission objected to the original award of licences because Austria's ORS was excluded, being owned by Austria's state broadcaster ORF. They now plan to launch in 2014.
Bulgaria makes DTT move | Broadband TV News
It's likely that the receiver specification will be the 'E-Book', IEC 62216, rather than the UK's 'D-Book' written by the Digital TV Group. This might cause some incompatible behaviour. It's unlikely that interactive content would work, as the 'UK Profile' of MHEG-5 is unique to the UK and Ireland.
For satellite, the Bulgarian channels appear to be on three different satellite clusters depending on the service operator. The main channels BNT 1 and BNT 2 are encrypted on all three, Satellite BG, Bulsatcomm and Vivacom and using different encryption systems to the UK (well, Vivacom are using VideoGuard, which is Sky's system, but you'd still need to get a card from Vivacom and the EPG may well download from a different place).
To pick up UK PSB channels you'd need a very large dish pointed at 28.2°E - far away from any of the Bulgarian services - as the free-to-air channels use transmitting dishes with a footprint designed to only cover the British Isles, at least at decent power/small dish size.
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Bob: The grey and strike-out are simply meant to indicate the services that close down. It doesn't mean it isn't happening.
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- http://www.rtenl.ie/wp-co….pdf lists the frequencies and powers used by Saorview transmissions at present. It appears (from comments on other boards) that they use 64QAM 2/3 8K 1/32 mode as used by the UK PSBs. The second multiplex is already broadcasting, but only carrying test loops.
Ireland actually received 8 UHF channels per site at the Geneva 2006 Regional Radio Conference, they aren't short of frequencies. Some of the assignments were above C60, which will be cleared in Ireland as it will here.
DTT was going to be mostly-pay in Ireland, as it was originally launched here, but the credit crunch hit them hard. Three different operators were awarded the licences before pulling out. They'd also be entering a market where Sky and cable providers are already hugely dominant; it didn't work here, where Sky's digital service and DTT launched at nearly the same time (although our low-power DTT and poor initial planning meant that getting all services was difficult for many viewers).
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Carl: Different DVB-T and DVB-T2 modes require greater or lesser amounts of signal, relative to the noise and interference on that channel. The ratio required depends on how much line-of-sight is available between the transmitter and the receiving aerial, and the amount of reflected signal that arrives at the receiver as well. The specifications give three scenarios: direct line-of-sight with no reflections and random noise; mostly line-of-sight with some reflection; all reflections and no line-of-sight.
The mode selected for the mini-mux requires 10.7 dB less signal (compared to noise + interference) in the first case, 11.1 dB less in the second, and 12.8 dB in the third, comparing to the mode used for UK PSBs. That makes it approximately equivalent to a PSB transmission with 11.7-19 times the power. It still puts Black Mountain NIMM well down on Divis PSBs (which will be at 100 kW), but in the direction of maximum power, actually not far off COMs, which now require 1.5 - 3 dB more than (1.4 - 2x) the PSBs. Brougher Mountain's coverage will be at least as good as the PSB multiplexes and far better than the COMs, while Carnmoney Hill's will be much greater.
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Briantist, Jeff Williams: BBC One HD will shortly launch national variants for Scotland, Wales and Northern Ireland (no date yet publicised, but it was in the DQF proposals, and in a work plan for 2011/12). However, regional variations are not yet proposed.
The main problem is actually cost of coverage on satellite. A single satellite channel is thought to be cheaper than a nationwide Freeview channel, even without Sky subsidising the costs (and then taking the revenue with the other hand), but each regional variant of BBC One has to be broadcast from the same satellites, so the BBC are effectively paying for 18 channels of space. On Freeview, very few transmitters broadcast more than one regional variant, so the costs don't multiply. (Caldbeck carries North East & Cumbria and Scotland, while Storeton carries North West and Wales, although each have directional antennas for one of the services.).
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Roy Hole: It looks like you're primarily a Crystal Palace viewer. If you retune on the Hannington dates, you should still get Crystal Palace services on the regular channel numbers. Your receiver should also store Hannington services on other channel numbers, but those numbers are not fixed in the specifications. I believe it's recommended that they are stored from 800 onwards, but some boxes just use the next number available after the first copy of all services have been stored (which will be around 312 or so), or fill gaps (there are gaps at 8, 35, 45, 47, 50-59 if you don't have HD, 53 and 55-59 if you do, etc) or use 1000 onwards. Some boxes don't store them at all.
Only the high-power BBC services from Hannington launch tomorrow morning. ITV1, C4 and C5 launch at high power on 22 February. The order you get may depend on whether you retune on both dates, or only after it completes. It's likely that ITV/C4/C5 channels from the South region would be stored before the BBC South set, as they will be on a lower frequency and therefore be found first.
Analogue television only carried a recommended channel number from the late 1990s, and again, there wasn't really a spec for where additional copies of the same channel should be stored, so different TVs may have behaved differently, or behaved differently in different parts of the country.
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Kieran R: As has previously been explained, Hannington has a 'notch' in its low-power digital coverage, with seriously reduced power transmitted to the east. This may be the cause of your current problems, though you have previously mentioned trees between you and the transmitter.
The high-power digital services will eventually transmit from the new main antenna, which does not have this notch. The notch is designed to protect reception of analogue channels from Guildford, so it cannot be fully removed until the London region switchover in April. The power will be increased to the maximum permitted, and the modes will be changed on 22 February, as advertised, however.
BBC A (Mux 1): 8 February (retune tomorrow after 6am)
D3&4, BBC B (Mux 2, B): 22 February
ArqA (Mux C): 4 April
SDN, ArqB (Mux A, D): 18 April
If you don't get all the muxes after retuning on 22 February, you will need to retune on the April dates to get them.
Digital UK's predictor continues to predict a good service for you on all multiplexes; between 22 February and 18 April the commercial muxes are predicted to be worse than now, as the power increase doesn't offset the additional margin needed after the mode changes. After the restriction is removed, 99-100% of locations in your grid square are predicted to get near-error-free reception 99% of the time. That figure *is* calculated on the basis of a good quality, reasonably high-gain, fairly directional roof-top aerial, with reasonably short downlead, without too many obstructions.
You've previously used Crystal Palace. That should be a good option for the PSBs but is expected to be poor for the COMs, as they will use the same frequencies as Rowridge. You're in the zone where Rowridge is too weak to be usable but still too significant a source of interference. The model used in predictions isn't as directional as most aerials actually are, so it may be better than predicted.
Do be aware when retuning that many boxes store the first version of the channels that they find, and any Hannington viewer may find that Crystal Palace is stored first - particularly when retuning after April, when CP will be 10 times its current power level.
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Luna: Check that the aerial is still actually present and pointing in the right direction. It will probably be pointing due east to the Black Hill transmitter, though there are other possible options.
If you're in a block of flats - which it looks like you are - you're probably using a communal aerial system. Check with your landlord, management agent or residents' association. If other people in the building have the same problem, the power to the distribution amplifier has probably failed/tripped out/fuse blown.
Analogue services in Scotland's central belt ended on 22 June 2011, and are being phased out over the rest of the UK this year. The remaining regions are the South-East (February and March, May and June), London (April), North-East England and Northern Ireland (October).
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Dave: You must be watching a different transmitter, the Hannington analogue services went at about 00:06 (BBC One)-00:18 (Channel 4). Unless you mean digital Mux 1 is still running, which I can't actually check - it's too weak, via my Crystal Palace aerial, to tune into. There's a bit more signal on C50 than on C46, and substantially more than on C45, so I assume Mux 1 is still running even though signal quality is shown as 0% for all those channels.
In your area, Hangleton, Brighton Central and Newhaven use the same channels for BBC One and BBC Two analogue as Hannington did up until today.
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Arthur Richards: The services are no longer in a one-to-one relationship with UHF channels. With digital, a single UHF channel can carry many services - at present, between 7 and 11 digital TV services per UHF channel. The combination of channels is called a multiplex.
You can find a list of the UHF channels used for each multiplex, and the services carried within it, at the top of the page. BBC One is carried in the BBC A multiplex on C61.
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Tuesday 4 October 2011 1:37PM
Brian: You presumably have a box that stores the first version of the channels that it finds. Due to the hot weather, the signals from distant transmitters have been coming through a lot more strongly and were - presumably - strong enough to be detected.
See Digital Region Overlap for tips on resolving this problem, although it may well go away if you retune once this spell has passed. For now, you may find the correct service somewhere else in the channel list, e.g. around 800.