All posts by Jim F
Below are all of Jim F's postings, with the most recent are at the bottom of the page.
Tony: Both the "One For All" aerials (SV9352 single boom and SV9355 triple boom) are Yagis not log periodic. Log periodics don't have the large reflectors at the back, so have low wind loading, but also have less gain. The particular advantage of the logs is that they're more directional, and two working together can be arranged to give good rejection of an unwanted transmitter.
Based on your location though, gain will also be important so if the new aerial works then carry on with it.
That does look like a good price for a T2 capable box!
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Mike: Post DSO, Belmont transmitter has 150kW on the three PSB MUXs, 50kW on SDN but only 8kW on Arq A and Arq B. What's interesting is that the four higher power MUXs are also on lower channel frequencies (22, 25, 28 & 30) with Arq A and Arq B higher up (53 & 60).
It could be that when you auto tune your telly, the first signal found is very "bright" and the tuner AGC adjusts accordingly. When it gets to the two Arq MUXs it may just miss them.
Try an auto scan with no aerial plugged in (to clear everything) and then manually tune just for the two Arq MUXs (on 53 & 60) first and check you get reception. Then manually tune for the rest of the MUXs (on 22, 25, 28 & 30) and see what happens.
The two Arq MUXs on Belmont stay at reduced power until 23rd Nov, when they get turned up to 100kW. That should put you back on track for an auto scan then.
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Gavin Richardson: You're just under 1km from Olivers Mount.
Pre-DSO, all MUXs were 100W, and post-DSO they're now 2kW (PSBs) or 1kW (COMs).
The power increase may be overloading your system, particularly if you have a distribution amplifier, and you may need to use an attenuator on the aerial input.
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Annie (& Alex): If manual retuning is telling you that the signals are poor, then I'd suspect adjacent channel interference from the existing analogue TV channels.
I've no idea whether they're using different antennas at Tacolneston (could be; its the sort of thing that happens in the run up to DSO), but that might explain your difficulty.
Different receivers use different filtering in the tuner, so some are less susceptible to adjacent channel interference than others (e.g. good quality PVR works when cheap TV doesn't).
It will cease to be a problem at DSO2 when the analogue signals have gone - that's on the 23rd November.
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David Hutson: You'll only get 4 HD channels from Rouncefall - same as any other post-DSO transmitter. One MUX is allocated for HD content and four programmes fill it up, so you'll get BBC HD, BBC1 HD, ITV1 HD & Channel 4 HD (i.e. no BBC2 HD or Five HD).
The complete line-up of programmes on Rouncefall gives you 16 SD non-subscription TV programmes plus the red button interactive screen, in addition to the HD programmes.
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Joe: The Sheffield transmitter at Crosspool is in the middle of its switchover, so you won't get BBC2 analogue because it has already been switched off. The rest of the analogue signals will disappear on Wednesday 24th Aug.
BBC1 & BBC2 are now on UHF channel 27, and retuning should find them - but if you haven't "cleared out" the previous UHF channel information for these, then your digibox will store them with programme numbers up in the 800s. Have a look there to see if that's what's happened.
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David Corrick: C47 on Wenvoe carries the HD channels only - you'll need a Freeview HD telly (or digibox) to receive it ("HD ready" on the TV doesn't mean it has a Freeview HD tuner, just that it has HDMI sockets).
At 13km from the transmitter, you're more likely to be getting signal overload causing the picture break-up, even with the tree in the line of sight, but traffic on the M4 motorway might affect your signal.
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Nick Fairweather: The Skriaig transmitter is unusual, in that it is a "main" transmitter that only transmits the 3 PSB MUXs post switchover (same as the relays at Inverarish and Penifiler, and it uses vertical polarisation too).
ITV4 is on the Arqiva B MUX, which is why you're not finding it at the moment. I've no idea if there are any plans to add the COM MUXs to Skriaig, but you have Freesat as an alternative.
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Brett: CP is a smidge East of due North from the Horley railway station (about half way between N and NNE).
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Tuesday 16 August 2011 10:30PM
chris: You may have a short circuit on your coax (either at the aerial end or at the plug that goes into your TV).
Alternatively, your TV may have decided that the signal from SC is too high, and has tuned itself to The Wrekin. Do you have any programme numbers in the 800s? If so, these might correspond to the correct transmitter and give better reception.
Try checking the coax cable and make sure that the channels you are receiving have the correct UHF channel numbers corresponding to SC.