All posts by Chris.SE
Below are all of Chris.SE's postings, with the most recent are at the bottom of the page.
Me Here:
Hi, there's often a delay before posts appear on here, I'm guessing you may have posted twice (from the count) thinking your post wasn't appearing, or got a fatal error message (ignore), it's annoying but the site owner hasn't been able to fix that! You may have to wait a few minutes for your post to appear!.
Thanks for the information about the TV channels on C22, that's definitely the Local multiplex from the Oxford transmitter, I keep forgetting about that one as unusually there are two used at Oxford!
This does suggest your aerial is pointing at Oxford, compass bearing 111 degrees - almost ESE, and the rods should be horizontal.
When you say you are physically unable to reach the aerial, is this because it's in an awkward spot? Can you see it? Or you just can't get into the loft anymore?
So something seems to have changed. Have your neighbours had similar troubles at all?
Sensible to ask, have you altered anything behind the TV yourself, moved any equipment or cables, switched anything on that wasn't on before?
As your aerial supplies two TVs, where is the aerial amplifier/splitter located and does it have an adjustable gain control?
One other important question, have you had a postcard from "restoretv.uk" at all?
Something you could try in the interim in case your TV's memory has got muddled.
Unplug the aerial from the set and carry out a full automatic retune. This should clear the memory as no channels should be found.
Plug the aerial back in and carry out a Manual tune on the following UHF channels -
The main multiplexes are C41, C44, C47, C29, C37, C31 and then C22.
That's in multiplex order BBCA/PSB1, D3&4/PSB2, BBCB HD/PSB3, SDN/COM4, ArqA/COM5, ArqB/COM6 and lastly the Local mux L-OFD.
Please post back with as much detail as possible.
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Me Here:
You aren't trying my patience at all. Nothing like a good technical challenge!
Unfortunately it's not possible to post photos direct, but one can post links to things on the Internet. A photo of the amp isn't needed but the model number (and make) would be ideal.
Most sets don't give any information about the multiplex name on the UHF channel, I listed them for you in the same order as I listed the UHF channels (they are all different for nearby/other transmitters).
This Freeview page Channel listings for Industry Professionals | Freeview which is usually up-to-date tells you which channels are on which multiplex.
The reason I asked whether you can "see" the aerial, even if you can't get to it, is just to check its orientation and that it hasn't moved from where you expected it to be. If of course it's not pointing where it should, what you receive will be different from what you expect to receive!
If you can't see it, do you have a friend or family member that could have a look? No need to actually get to it.
On the assumption that the aerial hasn't moved for some strange reason, and is pointing at Oxford (very likely as you are getting the Local mux) and as two sets are affected in the same way, and you've not changed any equipment etc. then on balance of probabilities there is likely to be two possibilities.
1) Something has gone wrong with the aerial amp/splitter or
2) A new (or upgraded) mobile phone mast has started operating close to you in the 700MHz band (just above current TV channels) and is wiping out all the higher channels, and restoretv.uk have not sent you a postcard (I've already known cases of the latter).
If it turns out to be mobile phone mast interference, then free filters are available from restoretv.uk but hopefully by process of elimination, we might be able to establish whether it's the amp or interference.
We'll work on the assumption that the coax from the aerial plugs into the amp/splitter using a coax plug and that the coax to each TV outlet also plugs into the splitter with coax plugs.
This is where the model number will provide a check on that and also how much gain it has (which will probably be important if it has to be replaced).
The usual method to see if it's the amp/splitter is to connect the aerial direct to just one TV outlet, bypassing the amp/splitter (and switching it off). If coax plugs are used as already mentioned, then we'd use a coax plug coupler such as this PHILEX Coax Coupler - Socket To Socket - Philex Electronics Ltd or, another such as eBay item 275343959468
(You need to copy any links here and paste them into the address bar of your browser. For eBay item numbers, open www.ebay.co.uk and paste the item number in the Search box).
A lot of (larger) supermarkets and of course TV/Radio shops sell these if you haven't already got one.
When doing this bypass check, ideally pick the one with the shortest cable runs to the TV outlet as any signal will be somewhat weaker. I wouldn't necessarily expect you to get the Local mux (usually the weakest signal) and you may not get all the others - but do a Manual tune on the UHF channels that I listed but NOT C22 as you already are tuned to it - if it's very weak you might still be able to see pixellated pictures etc, but retuning it will probably clear it.
(The reason for powering Off the amp/splitter is in case it's generating interference itself).
Post back with the amp/splitter model number (and any other information you can) and if you already have a coax coupler, the results of a bypass check if you are able to do one soon.
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Sally Lyon:
Thanks for your post Sally. It would seem highly likely then that this is mobile interference and there's no faults reported that I've been able to find for any of the TV transmitters you might use.
Both of you need to contact restoretv.uk for some free filters. The mast on top of the fire station tower certainly looks like one that could be operating in the 700MHz band just above the TV channels.
Put restroretv.uk into your web browser address bar. Play around with their web site if you wish, but it can tend the take you round in circles!
From the home page, click on FAQs at the bottom centre of the page, then on the FAQ page click "About Restore TV" towards the bottom right and select "Do I have to pay to call Restore TV?" which will open a window showing their freephone number 0808-1313-800.
When you get through to them, tell them that you've lost Freeview signals since they did work on the mobile phone mast at the fire Station, and COMPLAIN - why haven't they sent out postcards?
Tell them you aren't the only one affected and you've heard that there have been other cases where they've not been sending out postcards.
If you have an aerial amp/splitter the best place for the filter is between the aerial output and the input the the amp/splitter. If you cann't access it - eg. you may have an external one on the mast, then you are entitled to a filter for each TV set.
I hope they are helpful and don't give you any bull.
Please post back with how you get on.
Me Here: You need to do the same, don't waste any more time with checks at present.
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Michael Hanlon:
Some (6) channels are carried on a "Local" multiplex, however there are a limited number of Main transmitters that have a Local multiplex. This is a commercial decision in part, also availability of UHF channels, and they are transmitted on lower power and generally beamed towards the large urban centres of population they are intended to serve.
EPG LCN52 is one of them.
See Channel listings for Industry Professionals | Freeview for which channels are carried on which multiplex.
Unfortunately there are no Local multiplexes on transmitters in your area, nor are you predicted to be able to receive any transmitters that do have one. Your most likely transmitter is Redruth.
A lot of those channels are carried on Freesat if you have that. The lists above aren't up-to-date wit many of the recent changes - see Freesat's own site.
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Michael Hanlon:
See my reply to your other post at All of the free TV channels on PGSTART1650 in the UK | free and easy
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Brian Hitchcock :
Can't find any reported faults for the Plympton transmitter, nor its parent transmitter Caradon Hill and neither are listed for Planned Engineering.
Have you changed anything in your installation at all, moved anything - cables etc., got any new electronic or electrical equipment? Have you retuned for any reason? Check you are correctly tuned to Plympton's UHF channels.
Do check all the cables behind the TV or anywhere else that may have been disturbed. Sometimes bad connections can appear to only affect some multiplexes. The BBC multiplex is on UHF channel 40, the SDN multiplex (which carries 5USA) is on UHF channel 41.
Presumably your aerial is still intact and pointing in the correct direction, and the downlead isn't flapping in the wind?
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Dave:
Yes, you should get good reception from Durris. It's predicted to be good for the PSBs and a little less so for the COMs, especially ArqB/COM6 which could be Varuiable to Good. Have a look at which way your neighbours aerials are pointing to see how they get on. Reception might vary a bit across your postcode.
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Steve Beresford:
You are about 49km from Sutton Coldfield, Aerial needs to point at compass bearing ~207 degrees - fractionally west of SSW with rods (or squashed Xs) horizontal.
A Group K would probably be better than a Group B as it should give some protection from any mobile masts that may be nearby operating in the 700MHz band.
It'll probably need to be medium-high gain, but maybe a high gain K Group Log periodic may be best.
There is a Local multiplex on C36 which you aren't "predicted" to get, it's beamed N towards the Lichfield area and you are a bit off-beam as well as some distance away.
Have a look at your neighbours aerials just to see what the newer more shiny ones are to give you some idea.
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Saturday 5 November 2022 3:45PM
Mr Jon Stevens:
Firstly, frequent retuning is a very bad idea and is never recommended, especially if you have weak or no signal, or badly pixellated pictures. In most cases it will just clear the correct tuning and possibly tune to to a weak signal from another transmitter that will disappear as weather conditions change.
If you are getting Sky (LCN233) - that is carried on the ArqA/COM5 multiplex.
See Channel listings for Industry Professionals | Freeview for which channels are carried on which multiplex.
You won't be getting the signals from Bexhill as it is a "Light" transmitter and doesn't have any COM (or Local) multiplexes.
As this is a communal aerial, do any other people on the same aerial have similar problems?
If you provide a full postcode we can look at the predicted reception for your locale and the most likely transmitter.
Please have a look at which way (approx. compass bearing) the aerial is pointing and whether its rods (or squashed Xs) are horizontal or vertical. Can you see if its downlead is secure and not flapping in the wind?