All posts by Steve Donaldson
Below are all of Steve Donaldson's postings, with the most recent are at the bottom of the page.
Chris: Could it be an interfering mobile phone mast, I wonder? C48 is the highest channel now available for TV use, and thus closest to mobile phone signals.
Restore TV is the organisation responsible for resolving TV interference issues caused by mobile phone masts. Enter your postcode to see if they think you might be affected:
https://restoretv.uk/post…ure/
That your postcode does not show up does not necessarily mean that it isn't caused by a phone mast as such issues aren't so easy to determine. I would certainly question whether there may be masts that could be the cause, particularly to the front of your aerial.
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Chris: Restore TV has you down as having been sent a postcard, and therefore a mobile base station in the area potentially causing interference to TV reception. Speak to Restore TV and they should send out a filter to you. Let us know whether this cures the issue or not:
https://restoretv.uk/
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Chris: According to the Freeview predictor, Mendip is pretty much the only transmitter available in your area, so all aerials should be pointing the same way. Mendip is on a bearing of 254 degrees. 50 degrees would be almost the opposite direction. The elements on the aerial should be flat, meaning it is horizontally polarised. If the elements are "X" shape rather than straight/flat then the longer parts should be closer to horizontal than vertical.
Use the signal strength/quality screen on your TV and/or box. Don't just rely on whether the picture becomes visible or not. If you have more than one receiver (e.g. a box and a TV) then survey them all to see what information they give. Some might be more helpful than others in terms of the detail they give, as in quality and errors.
If there are any HDMI cables behind your TV, try moving them away from the aerial cable because they can interfere, potentially with one or two but not all channels.
Does the issue happen at particular times? Is it constant (when it does happen) or is it intermittent? Are there times when it doesn't happen?
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nick : Have you tried to receive the full complement of channels from Tacolneston?
Neither Tacolneston nor Sudbury are ideal, as there is much terrain in the signal path, including the Fresnel zone. Tacolneston is a bit closer too.
At DSO Tacolneston got a new, taller mast, and the transmission power was effectively doubled. All six multiplexes are at the same power (there are quite a few main transmitters whose COMs are at half power with respect to the PSBs).
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Chris.SE: It's funny you ask about radio amateurs because I spotted on Street View that there is a ham radio operator on Chris' road, judging by two large aerials towering above the rooftop.
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Ayub Bhayat: Do you normally get this channel, which is GB News? If so then there are engineering works ongoing and this might be the reason, the transmitter might not be on full power.
Many viewers will not see any difference with the lower power because they aren't in situations where the full amount is really needed. If you normally get this channel then perhaps you really need the full amount of power for the signal to reach you.
I don't know for certain that the transmitter is on low power. I am surmising as a possibility based on the assumption that you have lost this channel which you normally get *and* the fact that there is engineering works. If so, then the best advice is to sit it out and expect it to return to normal.
Don't retune because all that this will result in is loss of tuning. If you have retuned, then use the manual tuning section of your TV and scan UHF channel 39 (618MHz). If you have no joy with manual tuning, then wait a while and try again.
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Michael: Having reviewed your earlier postings, it looks like you may be in Ilfracombe. If you are still at the same postcode, then the Freeview predictor does not even mention Huntshaw Cross as a possibility, not even very poor.
You said previously about the co-channel interference to users of the Ilfracombe relay, caused by Carmel, and which varies by the tide. The ERP of the Ilfracombe relay is -4dB with respect to the former analogue, meaning there was an effective doubling of power at digital switchover, and maybe this was done in effort to compensate the co-channel interference from Carmel.
At 700MHz Clearance on 19/06/19 the Chambercombe relay became co-channel with Huntshaw Cross' COMs. So those in the vicinity with a Huntshaw Cross aerial will have found their COM reception wiped out by the relay! The predictor suggests the Chambercombe relay may be available at your postcode. If this is still where you are, do you get good reception of the Huntshaw Cross COMs?
There are clearly a lot of transmitters whose signal reaches the Ilfracombe area, whether strong enough to be watchable or not strong enough to watch but enough to interfere with another, desired transmitter. Judging by the predictor, there may be four six-mux transmitters in Wales to contend with, filling 21 channels. Post 700MHz Clearance there are only 26 channels left for TV.
The situation is brought about by the fact that the water is flat and without hills which would otherwise act to block unwanted, distant signals, but, further, the tide rubs in the salt by changing over time what's coming over. The other aspect is that the local terrain drops downwards to the water preventing or making difficult reception from a main station, thereby necessitating the presence of relays which require three channels.
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There are, of course, 27 channels available for TV post-700MHz Clearance, not 26 as I said. I made it to be 26 by subtracting 21 from 48, then subtracting 1 (to account for C38 not being used).
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Friday 29 September 2023 2:59AM
nick : Mont Lambert broadcasts on channels 34, 23, 30, 26, 37 and 32. Of those, C23 may well be not receivable due to interference from Aldeburgh (if it had otherwise been receivable).