All posts by Mike Dimmick
Below are all of Mike Dimmick's postings, with the most recent are at the bottom of the page.
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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Saturday 15 October 2011 7:32AM
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.