All posts by Chris.SE
Below are all of Chris.SE's postings, with the most recent are at the bottom of the page.
Andrea Williams:
LCN65 is TBN UK. That channel moved multiplexes several months ago to be on the PSB3/BBCB HD multiplex.
Unless your Auntie has a TV with an HD/T2 tuner then she won't be able to get it. Does she get any other HD channels eg. BBC1 HD on 101, BBC2 HD on 102, ITV HD on 103, Ch4HD on 104 and Ch5HD on 105?
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Julie:
You've posted on the DAB Radio page, but no worries. We really need a full postcode to provide an accurate check of your predicted reception, but assuming you are in Newbury and that your aerial is pointed at the Hannington transmitter (roughly SE of you), neither Freeview nor the BBC are reporting any problems at present and the transmitter isn't listed for Planned Engineering.
I would check that your aerial seems intact and pointing in the correct direction and that your downlead looks undamaged (especially if it is old). Also check all your coax plugs, connections, flyleads etc, unplug connectors check for corrosion or other problems and reconnect them. Flyleads are a common problem, try swapping/changing them. See what signal strengths and quality you are getting for the multiplexes (groups of channels) shown in your TV's tuning section.
Problematic connections, water ingress etc. can seem to affect reception of just an individual or several multiplexes.
Have you changed anything in your installation at all?
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Derek Hewitt:
Well that's very strange, you new TV must have quite a sensitive tuner if it's getting those signals with your aerial pointing at Waltham (you have checked it's still pointing the right way?). Cambridge would be the Sandy Heath transmitter so that would be received from a rear sidelobe of your aerial's reception pattern (SE direction), there could be a Yorkshire transmitter (Belmont) in a similar direction to Waltham (bearing 12 degrees ~N of NNE) but the predicted reception checkers aren't showing any such predicted reception.
I would unplug the aerial and do an automatic tune again. This should clear all the stored tuning as nothing should be found. Then plug the aerial back in to carry out a manual tune.
In the order PSBs1-3, COMs4-7 the UHF channels for Waltham are C32, C34, C35, C29, C37,C31,C55.
Predicted reception for Waltham at your location is Good for PSBs1-3 but could be more variable for COMs4-7, especially COM7.
Let us know if that works.
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Philip Davies:
Hmm, you shouldn't have any reception problems with all multiplexes from Blaenplwyf, reception is predicted to be good, although the COM multiplexes aren't so high power as the PSBs.
There shouldn't be any mobile masts close enough to give you any problems, unless there's a new one sprung up and can you see it and even then it's unlikely to just affect C25.
C25 is the COM4/SDN multiplex.
It sounds as though your set's memory could do with clearing and a manual tune carried out.
Unplug the aerial and carry out an automatic tune. This should clear all previous tuning as nothing should be found. Plug the aerial back in and do a manual tune -
The UHF channels are C27, C24, C21, C25, C22, C28 that's in the order PSBs1-3, COMs4-6.
For which channels are on which multiplexes see Channel listings | Freeview
If you don't have an HD/T2 tuner you can ignore PSB3/BBCB HD C21.
It might be worth you checking that your aerial seems intact and pointing in the correct direction and that your downlead looks undamaged (especially if it is old). Also check all your coax plugs, connections, flyleads etc, unplug connectors check for corrosion or other problems and reconnect them. Flyleads are a common problem, try swapping/changing them. See what signal strengths and quality you are getting for the multiplexes (groups of channels) shown in your TV's tuning section. It should be pretty much the same for all the PSBs and maybe only fractionally less for the COMs.
Problematic connections, water ingress etc. can seem to affect reception of just an individual or several multiplexes.
Also make sure you don't have any HDMI leads near unscreened/poorly screened flyleads/aerial leads as that can cause interference.
If you have any amplifier/splitter, does it have a variable gain control? If so, turn it down a touch, too much signal can also cause the sort of problems you've seen. Be aware that when there is too much signal it is possible for the strength reading to show less - it doesn't mean the signal is less!! Problems can of course occur with certain weather conditions, interference from distant transmitters - tropospheric ducting - https://www.bbc.co.uk/rec….jpg see also Effect of tropospheric ducting on Freeview | RTIS
Let us know how you get on.
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Julie:
This is the Analogue page, not DAB sorry, but now I see you've posted there as well!
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Julie:
Did you not see my reply on the other transmitter page? Here is a link
Newbury (West Berkshire, England) analogue radio transmitter | free and easy
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Mac Fletcher:
As StevensOnln1 says, a full postcode is needed to look at predicted reception. Sometimes aerials successfully receive signals off side-lobes and to the rear of an aerial. You could try a manual tune of UHF channel 40 which the one used for the Local Multiplex from Sutton Coldfield. The signal is beamed in ~ a WSW direction AFAIK and you may just be on the edge of it.
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bruce tearle:
Your predicted reception is excellent. Are your signals back?
It seems to be up and running with pretty much normal signal levels on all multiplexes. I can't find any fault reports listed at present.
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Sunday 19 July 2020 7:58PM
Andrew:
Your receiver ought to cope quite happily with 54% signal providing the quality is 100% but even that could drop a bit without too much of an issue. A lot depends the causes of any signal variation.
The main issue with COM7 being a SFN (Single Frequency Network) is there are "not" spots where there's a weaker signal due to interference from the other C55 SFN transmitters which will sometimes vary with weather conditions. There;s been some variable Tropospheric Ducting about off and on for a while see Effect of tropospheric ducting on Freeview | RTIS though that's not as good a pictorial representation as they used to use, see https://www.bbc.co.uk/rec….jpg
Interference can come from transmitters in Europe as well which doesn't help!
When you have high signal and 0% quality, there could be two reasons. Lots of interference (so high signal) and signal not decodable so 0% quality, or as you are aware, overload can be an issue - not necessarily from the C55 signal but the others. This can result in the indicated strength going down (even though the signal is stronger) as automatic gain in the receiver goes down but how/if this happens can vary with different sets/manufacturers Even if the indicated strength hasn't gone down due to overload it can mean the weaker signal doesn't decode, or you get pixelation and/or sound break-up.
Trying to get some happy compromise when the receivable multiplexes are different strengths can be a real problem. I would go for a variable attenuator such as
Coax TV Aerial Attenuator Adjustable Variable Between 0-20 dB Reduces signal | eBay eBay item:310039226920 or
VARIABLE TV ATTENUATOR IEC 0 - 20dB (5 - 1000MHz) SATELLITE TV DIGITAL FREEVIEW 5057708221423 | eBay eBay item:362541254551
The brand seems reliable, there are other suppliers, some at rip-off prices!
That would enable you to tweak things and see what is going on as you vary the attenuation. It may not solve the problem, although the signal strength for COM7 hasn't altered with the changes and retune, some think it may not be quite as resilient now that the multiplex is completely full.