All posts by Jim F
Below are all of Jim F's postings, with the most recent are at the bottom of the page.
Janice Wilson: Looks like you're suffering from Co-channel interference. CP transmits the HD programmes on UHF channel 31. The SDN MUX on Sandy Heath was moved to UHF channel 31 on 31st August (a temporary "parking channel"). Although SH is north of you, and your aerial is pointing south to CP, there's enough signal being received from SH to cause interference.
The bad news is that SH doesn't adopt its final channel for the SDN MUX until 9th May, which is after CP has undergone DSO (DSO1 is on 4th April, DSO2 on 18th April).
Digital UK's predictor suggests that you can't receive the HD MUX at all at present, through until 18th April. Reception of the HD MUX should be possible from SH, but that means realigning your aerial. Reception from SH is shown as good up until July next year; but reception from CP will ultimately be the best choice (after DSO2 there).
Tricky to decide what to do!
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Alison: Put your SkyHD box on, showing a programme. Then on the SkyHD remote press "Services" then "0" then "0" then "1" then "Select". This will bring up the installer menu.
The RF Outlets tab will show the UHF channel in use (default is 68), and whether the RF2 9V power is ON or OFF.
Some distribution amplifiers use the 9V power from the RF2 socket to operate, so try turning that ON and see if you have any more luck. Remember to save any changes you make (green button).
You'll know from the SkyHD box which analogue UHF channel to look for on the other TV sets.
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SB: Using ST13 5DR as a nominal post code, coverage is possible from both Fenton and the local Leek relay.
DUK's postcode predictor shows that you can't receive the COM MUXs from Fenton - this is because they are co-channel with Fenton's PSB MUXs (which makes reception of Fenton non-ideal, hence orange colour on DUK trade view).
Reception from Leek PSBs is shown as good (but no COM MUXs transmitted from there).
Your receiver may be able to indicate the UHF channel numbers you are receiving at present (Fenton: 24 & 27, Leek: 25, 22 for BBC A & D3&4 respectively).
Sutton Coldfield shows all green, but would depend on your location in Leek, and you'd need a horizontally polarised aerial (Group B or wideband) pointing slightly east of south.
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Tim: Would it be possible to try connecting your aerial directly to one TV only (i.e. bypass the distribution amplifier)?
This would give an indication on one TV of the signal strength / quality direct from the aerial.
I don't know if you have a masthead amplifier (which could be powered by your distribution amplifier). If you are then the masthead amp would need power (otherwise you'll get nothing at all). The combination of a masthead amp and a distribution amp might just have too much gain, which can give the effect you describe.
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Chris: DUK show March 28th next year as the date for the COM mode change (SDN from 2k to 8k) and power up.
N.B. There's a retune event this Wednesday (28th) - all three COM MUXs change channel and Arq A changes mode (16QAM 2k to 64QAM 8k). Don't know if you may get some interim power increase at the same time.
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Terry Metherall: I think Winchcombe had the BBC A MUX on UHF channel 61 between DSO1 and DSO2. At DSO2 it has been moved to UHF channel 49.
Resetting your Freeview box by doing a "first time installation" or "default settings / factory reset" should sort it out.
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David Painter: Looks like you're seeing co-channel interference from the Keighley relay, which uses UHF channels 58 and 61 (but these were in use for analogue prior to DSO). Analogue power was 10kW for Keighley. Post DSO power is 2kW, which means the digital signal will go "further" than the analogue signals, or cause more interference.
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Nick: Max. cable distance for a standard mini dish is getting on for 50m (that's around 15dB loss for good quality coax - i.e. the stuff that is copper rather than copper plated steel or aluminium).
A bigger dish will provide more signal, so can tolerate a larger loss, and you can get amplifiers powered by the satellite receiver up the coax to overcome some cable loss.
At 25m max. you should be fine, unless you're living way up north.
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buontempo: Probably - Conquest House will be the location for the new Bexhill relay which comes into operational at DSO in your area (May next year). This will be a relay of Heathfield (rather than Hastings), but I don't think it is transmitting at the moment.
The interference you describe sounds more like taxi services - I've no idea what's on the top of Conquest House, but PMR transmitters (used by taxi companies on tall buildings) do cause interference, and perhaps a new antenna has been put up there.
Your block of flats may need an interference filter adding to the communal system to cure the problem.
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Saturday 10 September 2011 6:41PM
Paul777: You could buy a reconditioned Sky+ or SkyHD box to save having an additional item taken up a 13A socket.
What you're asking for is a power supply similar to that used for powering a masthead amplifier (coax connectors with 12V DC on one side that connect to the aerial, but in your case needs to go to the magic eye. The other DC blocked side needs to go to the Sky box RF2 connector).
I've not seen a masthead power supply with a 9V output, and 12V is more than the specified 9V from the RF2 socket - but I have seen this arrangement work in exactly your situation. However, I can't say I've tried this with every make of magic eye.
Losing the 9v power from the RF2 output is a relatively common failure for Sky+ boxes.