All posts by Chris.SE
Below are all of Chris.SE's postings, with the most recent are at the bottom of the page.
Adrian:
The very variable terrain in your locale gives some very variable predictions depending on precise location. In some spots I can get predicted reception from Kendal (closest), Lancaster, Windermere and Winter Hill. Windermere being the worst in some spots!
I have a thought or two but it depends on what you reply to my previous queries.
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Richard quakkelaar:
Yes the info for the PSBs seems to have disappeared from all transmitter pages, no doubt due to a bug resulting from automated site software "upgrades" (not sure that choice of words is best!!). I know the site owner has had a few issues that some of the upgrades have created.
I believe this is the info you want -
PSB1 & PSB2 - DVB-T 6817 (8K) carriers, 64QAM mode, FEC=2/3, 1/32 guard interval, MPEG2, Mux Bitrate 24.1Mbps
PSB3 - DVB-T2 27841 (32KE) carriers, 256QAM mode, FEC=2/3, 1/128 guard interval, MPEG4, Mux Bitrate 40.2Mbps
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Stu:
Hi Stu. You may have noticed 3 posts before yours that the Oxford transmitter is having Planned Engineering, so that may not be helping the situation as IIRC you are not in the best of locations for reception.
However, that said, the fact that is blipping up and down is a touch odd. Now, there is some very marginal "Tropo" just passing affecting parts of central England, but that should be gone by the end of the day, whether that is contributing to the issues is difficult to say.
Put your full postcode into https://restoretv.uk/post…ure/ if it says Yes, even if you haven't had a postcard from them get in touch with them and request a free filter (0800-1313-800). It could be a new/upgraded phone mast now giving problems.
I assume you've checked your aerial is still pointing correctly, coax ok etc. If you still get sufficient strength with the amp/splitter out of circuit, see if the quality then remains stable. If so, it could still be interference causing the problem and now it's not getting amplified it's not having the same effect., and so hopefully a filter (before the amp/splitter) may cure the issue if it's not the engineering/weather.
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Ian Jackson:
There's been a lot of engineering work on many main transmitters this year and some people in weaker signal areas have had some reception difficulties due to the work, some as noted on the Freeview page (this is the DAB page).
When you say "it" keeps moving your BBC channels can you be explicit - moving which ones where?
Does it end up tuned to another transmitter maybe Oxford instead of Sandy Heath?
You certainly shouldn't need to retune everyday, not a good idea, especially with the engineering work going on, which may be related to your issue. If you go into the TV Tuning/Programming settings, there maybe an option to tune off the Automatic Updating. It is certainly better off than on, such settings are more trouble than they are worth.
If it's another issue, how old are your TV sets? If they are very recent Freeview Play devices the this could be as a result of CLM - Channel List Management, if it's simply swapping BBC SD and BBC HD channels.
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Stu:
Hi again. How old is your amp/spliiter?
Unless it's very new, the chances are that the filter in it, is what is often termed a 4G/LTE filter for 800MHz. The spec. for it should tell you.
These days you need what's often called a 5G/700MHz filter (sometimes LTE is also mentioned) but 700MHz is the important bit. Such filters will also clobber the 800MHz issue.
If that postcode check for restoretv said YES you should definitely get one.
I didn't think there was any "Tropo" this week but did a precautionary check, it's so marginal and only predicted today over a relatively small area, I'd be surprised if it was having much if any effect except in a few isolated cases. Such things are "predictions" and I wouldn't take it as gospel.
See if things are more stable tomorrow.
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Adrian:
Hi again. Another thought, should have remembered to ask, has your masthead amp got variable gain?
If so, turn it down a bit until the Signal strength drops just below 100%.
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Ian Leslie Jackson:
"I/we" are not working on a transmitter, this is an independent FREE Technical helpsite.
Freeview publish a list of Planned Engineering (provided by Arqiva & DUK) and that data is collected by this site and published on the relevant transmitter page. There are separate pages on this site for Freeview, DAB and AM/FM, however the information may appear on more than one page.
Arqiva, who are the company responsible for the great majority if transmitters in the UK, never give any details of what the work entails or how long it will last especially as some of it may be weather dependent which means delays can happen as you can't climb masts, service antennae, cables, guy ropes, etc when weather is unsuitable.
Now that you've provided the information about how the channels are moving, this particular channel allocation is normally a clear indicator that when retuning you are picking up another transmitter from the (correct) one you are normally tuned to and it's often a different region. When a set is picking up more than one region it will usually put the weaker ones in the 800s unless the set has the provision for setting your preferred region or postcode - even the latter is sometimes a problem when in weaker reception areas.
The (strong) advice for retuning is simple. IF you are correctly tuned to your normal transmitter's UHF channels then do NOT retune when the set shows No Signal or has badly pixellated pictures, sound breakup etc. This includes any "Auto-retune". The only time that retuning may be required is if/when any of the commercial broadcasters change their channels on any of the COM multiplexes, and usually you get a pop-up message when going to the affected TV Channel (LCN).
It does not matter whether the cause of the No signal, bad pixellation etc is due to transmitter engineering, weather conditions causing interference, or local interference, or even faults on your own aerial system, retuning will NOT help. You cannot tune to signals that are not there or can't be decoded. The net result is often the correct tuning is cleared and/or the results you've been getting.
Your specific problem is two fold and is
a) down to your Panasonic set having an auto-retune function which (it seems) cannot be turned off with the current firmware (such functionality is a pain and is frequently far more trouble than it's worth as you have discovered!).
and
b) due to you being in a weaker reception area for your chosen transmitter (region) where you can also get signals from other transmitters (regions). This being compounded by weaker signals with some engineering work.
Aerials have what are called "side-lobes" which can pick up signals from certain directions on the sides or rear of the aerial, albeit they will be much weaker than those in the direction the aerial points. So if you main signals are weak or missing, the set can sometimes find those picked up on sidelobes if they come in strong enough.
In your particular locale (dependent of exact location due to terrain, nearby buildings, trees, other structures etc) you may receive signals from 3 main transmitters - Sandy Heath, Oxford and Crystal Palace, the latter being weakest.
The cure to the problem is to turn off any automatic updating. In your case keep hassling Panasonic (or for anyone else in a similar situation - their set manufacturer) for a firmware update if you cannot currently turn it off.
Just also worth noting, that it's a good 10 years since DSO and many transmitters will have needed extensive maintenance etc to ensure they continue to provide reliable transmission during the worst of the weather conditions we may see, etc.
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Tuesday 7 November 2023 6:03PM
Adrian:
Hi there, well that's good of them to send an external filter even if has no effect/is not essential at present, it'll give you good protection for the future.
Do you still have that 4G filter? Was it an internal one with coax connectors? I'm a little concerned about the fact that you have 100% signal there fairly consistently, as too much signal can be as bad as too little, as overloading of the tuner front end can cause similar issues.
I'm thinking if your still have it and it's coax try it before the TV and see what happens to the signal strength (as well as the quality) as it will give a little bit of attenuation. Ideally we want to be down a touch from 100%.
If it's not coax or you don't have it, do you have any attenuators - you sound like the sort of chap that might have. If so try one before the TV, again to see what the effects are.
I'm concerned about using the higher gain log periodic at present with figures like that until we've a better feel for what is happening.
As for reception from Kendal, hmm, well the predictor doesn't give any :o
As you've obviously had good stable reception from Windermere in the past, then it's the one to stick with we just need to discover why it's become unstable.
Another thought, do you have a multimeter (preferably digital but no matter) check the PSU for the pre-amp, both disconnected and connected to the mast head and check it's ok.