All posts by Mike Dimmick
Below are all of Mike Dimmick's postings, with the most recent are at the bottom of the page.
Briantist: Arqiva's Reference Offer for Local TV says that the chosen antenna design for Waltham is 'Crossed Logs @ 100 degrees - 4 Tiers', at 157m above ground level, on a bearing of 40°. It does seem that this is intentional.
http://www.arqiva.com/doc….pdf
We shouldn't forget that the multiplex will also carry two more channels - perhaps there was a desire here to try to cover the East of England at least a bit, since Tacolneston will mainly transmit to its north-east, and Madingley to its east (you haven't updated the Madingley page with these details). Sandy Heath is in the Reference Offer - aerials pointing to the west - but the Bedford licence hasn't been advertised, as far as I know.
An aggregate map showing where there are holes in the overall coverage would be interesting, for the two services that Comux are allowed to run.
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Drew: No. BT are only offering it to Infinity subscribers on YouView. Infinity still uses copper cables from the roadside cabinet to the home, but the fibre connection is extended from the phone exchange to the roadside cabinet. This means that the run of copper is much shorter, so much higher speeds can be offered.
The channels are being broadcast over-the-air for old BT Vision boxes, for those who aren't in an Infinity-enabled area. Those boxes have a slot for a decoder card that decrypts the transmissions. YouView deliberately left the decoder card slot out of the specifications - the intention is that over-the-top pay services will all be delivered over the Internet.
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Bertie: BBC ALBA has only ever been available on Freeview. You must have a Freeview tuner in, or accessible by, your TV somewhere.
You probably need to press the Source/AV button repeatedly until you get back to the Freeview tuner - this will probably be labelled 'Digital' or 'DTT', unless it's an external box in which case it could be AV1, AV2, etc. On some TVs you press Source/AV then scroll up or down to select a different source, or press the coloured buttons.
The behaviour you're seeing with the Sky box is because it contains an RF Modulator - a component that converts its output to an analogue TV signal that can be tuned in, as if it were coming from a transmitter. This is really a legacy of old TVs that could only tune into over-the-air transmissions, and didn't have any other inputs. Now that analogue TV transmission has been switched off, it will be the only thing that the TV's analogue tuner can find.
There have been some changes in the frequencies used in the north of Scotland in the last few weeks, to free up the highest frequencies for mobile phone services ('4G'). However, no changes were made at Skriaig, so this shouldn't have affected you.
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Robert Taylor: The problem is that signals carry over a long distance to cause enough interference to prevent reception, even if they aren't strong enough to be receivable. Just because frequencies aren't being used at your chosen transmitter, doesn't mean they *can* be used there - if they were, they would cause reception problems elsewhere. Or, alternatively, because they are being used elsewhere, that would cause too much interference for them to be used effectively where you are.
Channels 50, 55 and 59 are in use at Weaverthorpe, Whitby, Castleton, and a number of locations in West Yorkshire. Channels 51 and 52 are in use at Emley Moor. C56 is relatively lightly used across the country, which is why it will be available for a local service, but (if used) it will broadcast from different aerials further down the mast, and pointing only at Scarborough itself, not the surrounding area.
Signals also carry strongly enough over the sea to still be a problem in northwest Europe. For the 600 MHz band, Ofcom have had to co-ordinate Olivers Mount with Holland. However, the cost of implementation relative to the amount of coverage achievable means that Olivers Mount is not in the set of 30 transmitters that will be getting the service.
The only space we have in the plan to put new channels is the so-called '600 MHz band', channels 31 to 38 (550 - 614 MHz). This is because Ofcom planned a gap there, so it could be sold off. It became clear that since this wasn't co-ordinated with any other countries, any hardware would have to be UK-specific, and we're not a big enough market for the mobile phone makers to do a specific build - therefore there was no demand from the networks. As a result, there's now an opportunity - but it has to be done cheaply and quickly, as Ofcom are suggesting they will steal it back in five years' time.
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Ian: call 0333 31 31 800 (local rate) or 0808 13 13 800 (free from landlines) - I found that at Contact at800 / DMSL | General Enquiries | at800 .
at800 are sending postcards to addresses that could be affected: Will 4G masts affect Freeview in my area? | at800
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Lester Barker: Channel 4+1 has been on Freesat practically since it launched - it went free-to-air in September 2008. You should find it at channel 121.
If it doesn't appear in the guide, try turning the box off and back on. If it still doesn't appear after turning the box off and back on, look for a Factory Reset or Default Setting feature. Typically, the default password for this is 0000 or 1234. If neither of these work, or the box's manual doesn't say, contact the manufacturer to find out how to reset the password.
There are six variants of Channel 4+1, which have different adverts for different parts of the UK. They are all carried on the same frequency. The box uses the postcode you enter to decide which variant to put in the programme guide.
If channel 121 does appear in the guide, but you don't see anything when you select that channel, even after doing a reset, it indicates a problem either with the vertical element in the LNB (the box on the arm of the dish), or with the signal that selects vertical polarization. Make sure you haven't split the cables from the dish to the box - trying to connect more than one box to the same feed cable causes a conflict with the selector signals that the boxes are sending to the dish. Each input on each satellite box must have its own separate cable to the dish, and its own input on the LNB.
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Jo Moor: If it's like my UE26EH5000, you simply need to do an Auto Retune.
Looking at the manual for your TV, you should press the Menu button, then select Broadcasting, Auto Tuning. The previous channel list will be deleted and the channels will be detected from scratch.
My TV asks whether I want to retune analogue channels, digital channels or both. I just select 'digital channels' since I don't have any analogue equipment.
If you're using the Touch Remote, press More then press Menu on the touch area to get to the menu.
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Trevor Harris: The satellite has a UK (OK, British Isles) footprint transmitting dish. As far as we know, any transponder's output can be routed to any transmitting dish, it's up to the leaseholder for the transponder to decide whether they want a European footprint, a West African footprint or a UK footprint.
The Astra 1N satellite is still supposed to move to 19.2°E at some point, it was only a stop-gap to cover the early retirement of the 2D satellite. (1N's UK footprint isn't really a UK footprint, it's the best that could be achieved by steering one of its dishes - designed for some other purpose.)
You're right that "Freesat" doesn't lease any transponders itself. They would probably benefit from being a broker to allow channels to launch without having to lease a whole transponder from SES - as Sky do. But Freesat is a marketing joint venture between the BBC and ITV plc, and doesn't have much capital of its own.
I note that Arqiva have now signed a deal with SES for a lease on multiple transponders:
SES AND ARQIVA SIGN CAPACITY AGREEMENT FOR THE UK MARKET - SES.com
. I think it's likely that Arqiva will use this to supplement their large investment in Freeview - offering FTA satellite coverage to the channels they already carry on Freeview - and as a hedge against the government deciding to switch off large chunks of Freeview spectrum.
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Charles Stuart, Aerialman: BBC Three HD and CBBC HD will be on the BBC B/PSB2 multiplex along with BBC One HD, BBC Two HD, ITV HD and 4hd. They will replace BBC Red Button HD soon - expected to be after the Doctor Who 50th Anniversary special on 23 November. That programme was made in 3D, but since BBC One HD cannot show 3D content (there are compatibility problems with some equipment), the 3D version is expected to be simulcast on Red Button HD.
Mendip is expected to be quite late in the rollout programme because it needs a new broadcast antenna: its current PSB and COM antennas are not capable of handling the allocated channels.
Sutton Coldfield is expected to get the service in December. It has the second-highest population coverage of any transmitter in the country. I don't think Arqiva can reach a 50% population coverage with Crystal Palace and Sutton Coldfield alone. Given their press release HD channels on Freeview to reach double numbers - Arqiva says they 'will be available to over 50 per cent of UK households, including coverage in all nations, in time for Christmas', I suspect that means Black Hill, Wenvoe and Divis are now slated for December as well.
The last rollout plan I saw was in Arqiva's Reference Offer for transmission, http://www.arqiva.com/doc….pdf . The press release's promise to get 70% coverage by June would suggest an accelerated rollout, however (and the indicative coverage tops out at 68.8%). Perhaps the weather has been kind.
The Wrekin is not one of the sites slated to get this service. Although it used frequencies in this band before switchover, it had to give them up so that Sutton Coldfield and Winter Hill could use them instead. Their greater population coverage trumps the earlier allocation.
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Tuesday 6 August 2013 7:10PM
Actually that Waltham pattern is a bit odd. I can't see any reason for the lobe pointing to the east, which I would generally assume would have to be another stack of panels from those pointing slightly north-west.
It has to be a new array rather than reusing one of the PSB or COM arrays, because they're at the top of the approximately 280 metre tall mast. The Local Multiplex document gives the antenna height above ground as only 151 metres. The low-power DTT panels were still installed between the new main antenna and new reserve when the last set of photos on MB21's Transmission Gallery were taken: mb21 - The Transmission Gallery
It's not in preparation for the 600 MHz band either: Ofcom's list of international clearances shows no significant limitations requested by Belgium or Holland, and Arqiva's reference offer says they're going to use the main antenna.
http://stakeholders.ofcom….pdf - sadly, no restriction plots given
http://www.arqiva.com/doc….pdf