Missing channels on Freeview Box

[Lucky Luke]

Hello boffins. I live in the UK, of course, and our Freeview box is a Panasonic, which worked well for years. It still does, mostly, but in recent months, it has not been able to garner an entire "multiplex" (I think that is the term) of channels that used to show up unfailingly when I re-tuned the box (to accommodate new channels, so as not to cause errors when recording). As you will know, there are several tranches ("multiplexes"?) of channels that are detected when re-tuning is happening. For years, the last tranche of channels (numbered 37) including TalkingPictures TV, always appeared last. Then, a few months ago, this group of channels stopped being detected and gathered on the box. Nothing had changed in the cables, aerial etc. that I know of. This went on for some long time. Then, there was a one-off gathering of multiplex no. 37.When this happened, I thought that the trouble had corrected itself. However, the next time an alert appeared on the screen, saying that a new channel was available, as usual, I re-tuned. Once again, no multiplex 37 appeared! And that is the way it has stayed, ever since. I should like to have access to TalkingPictures TV, in order to record the occasional film.

When I consulted the Freeview website and entered my postcode etc., the verdict was that multliplex 37, including TalkingPictures TV, was available. Whether "available" or not, this group of channels is not detected and gathered on the box.

Can anything be suggested by anyone that would cure this fault? Of course, I have tried unplugging the box, making sure that the aerial jack is tightened as much as possible etc. I don't have much technical knowledge.

With thanks in hopes of a helpful response,
L.L.

 

[opps]

If I had to recommend a forum member off the top of my head, it would be @Lucid . Other than that, sorry, I can't help you. I may be useful if you take photos of the aerial/etc.

Good luck.

 

[Murdochcat]

Has your aerial moved at all? Have you got tall buildings being built nearby?

 

[Rodders53]

Or me TV Reception Advice was a well paid job for me, last Century.

Location (a very nearby postcode of shop, pub, church or school) will pin point the likely transmitter(s).
Lancashire is likely Winter Hill or Lancaster or one of a few others. Arqiva B aka Com 6 of WRH is frequency channel 37, though, and has Talking Pictures among others...

TV aerials and cables age. Performance can drop off. Weather degrades materials by UV damage and water ingress. Winter Hill used to be a group C/D aerial, but now used mainly group A channels. Old aerial may not perform as well or uniformly?

Fettle / remake any hand made aerial plugs and sockets. Check they seat firmly in TV and any pvrs or aerial amps (boosters). Ensure any HDMI cables are well apart from the aerial cables - cross interference is known to happen. Try alternative moulded fly lead if they are being used and you have others. Same for hdmi, to rule out a faulty one.

Use the TV's manual tuning and diagnostic signal meter to see if the signal levels in all the receivable mux frequencies are good, middling or poor (as well as f.ch.37). Report those numbers of you can it may and diagnosis.

 

[Lucky Luke]

Or me TV Reception Advice was a well paid job for me, last Century.

Location (a very nearby postcode of shop, pub, church or school) will pin point the likely transmitter(s).
Lancashire is likely Winter Hill or Lancaster or one of a few others. Arqiva B aka Com 6 of WRH is frequency channel 37, though, and has Talking Pictures among others...

TV aerials and cables age. Performance can drop off. Weather degrades materials by UV damage and water ingress. Winter Hill used to be a group C/D aerial, but now used mainly group A channels. Old aerial may not perform as well or uniformly?

Fettle / remake any hand made aerial plugs and sockets. Check they seat firmly in TV and any pvrs or aerial amps (boosters). Ensure any HDMI cables are well apart from the aerial cables - cross interference is known to happen. Try alternative moulded fly lead if they are being used and you have others. Same for hdmi, to rule out a faulty one.

Use the TV's manual tuning and diagnostic signal meter to see if the signal levels in all the receivable mux frequencies are good, middling or poor (as well as f.ch.37). Report those numbers of you can it may and diagnosis.

Thank you for all the detailed information, Rodders53. Winter Hill is the transmitter, as I discovered earlier from the Web. I suppose if there is any degeneration of cables, aerial etc., it would take far more time than I have, to find it. I shall do what I can to make sure that the HDMI cable is not crossing over an aerial cable — this is the easiest bit. What I can't understand is how it was able, just once in a long time, to detect frequency channel 37, then return to the non-detection again.

All the advice you offer is good, Rodders563, I am sure, but I don't have the time for messing about with technical matters like signal meters etc. (I'm too involved in sharing household chores with my ailing wife). If the HDMI cable is not involved, I shall have to take the easy way out, and accept the non-reception of TalkingPictures TV. Thanks again, though.
L.L.

 

[Lucky Luke]

Has your aerial moved at all? Have you got tall buildings being built nearby?

I have no reason to believe that it has.

Has your aerial moved at all? Have you got tall buildings being built nearby?

No, there are no tall buildings.

 

[Rodders53]

Fettle those cables and connectors. Most problems are caused by poor connections.

Signal meter measurements can be taken at a quiet moment, when you have some down time. They should not take long (once you find where they are in the TV menu system).

OR pay a professional to come in and fix it. All 6 muxes should be equally received and if those channels are desired then it may be worth the expense. (Although check if they are streamed over the internet and you can watch that way for no added cost).

 

[Lucid]

The Winter Hill muxes go down Ch. 21. If you have a group C/D aerial - something tuned for optimal reception from Ch.48 to Ch.68 - its reception will go lower, but by about Ch. 26 you're flogging a dead horse. For a home in a high field strength area, a bit of poorly shielded coax might be pulling in more signal for the lower frequency muxes than the aerial itself.

credit to aerials & TV for their graph.

In all likelihood though, the aerial is probably one of those 'wideband high-gain' models. A Group W aerial. If that's right, then @Rodders53 is on the money about aerial and cable degradation.

Odd things can happen with aerial systems. If you rule out simple stuff such as a plug being partially connected, or a poorly shielded fly lead allowing the signal to get knocked out by RFI from a HDMI lead, or a badly-designed switch-mode power supply bleeding out RFI, then what's left is the more obscure issues such as notch filters. This is where something like a trapped cable or a corroded connection still works except for a narrow range of frequencies. If those happen to coincide with one of the muxes the property would normally receive, then sure, you could lose the mux on Ch. 37 and still get the others.

Most decent TVs have the option to look at signal condition as part of the tuning menu. How you get to it, and the depth of the level the tools go to varies from brand to brand. My Panasonic TV gives me signal strength and signal quality. There's a bit error display along with the network name (North West, in my case), and there's the frequency and the channel displayed. It's not as accurate as my meter, but certainly good enough for a bit of quick troubleshooting.

I'm on Winter Hill, too. It's about 30 miles due north. Ch.37 is on 602.00 MHz.

If you've doublechecked the simple stuff such as plugs being pushed in all the way, and looked for more obscure causes such some bit of coax sheath - the outer insulation - stretching enough that the inner core starts to disengage from the plug it's supposed to be attached to, then what's left is the stuff which you may or may not be able to do something about. Replacing the aerial and the coax is probably going to be the answer.

 

[Rodders53]

Back in the 90s the Triax Unix 52 C/D was re-designated W as it went down rather well into A. But all widebands tend to be lower gain at A than C/D frequencies (except Log periodics and Grids), which was useful as cable losses are greater at the higher frequencies.

When WRH was changed to group A (circa 2020?) there was a free aerial upgrade scheme that affected viewers could apply to... far, far fewer aerials were replaced than expected.

I've had (still have one) Panny TVs that showed post-AGC signal strength and post error correction Q (10/10 on both pre and post DSO when the power emitted increased tenfold from Tacolneston). Their more modern sets are a lot better at informative metering.

 

[Lucky Luke]

The Winter Hill muxes go down Ch. 21. If you have a group C/D aerial - something tuned for optimal reception from Ch.48 to Ch.68 - its reception will go lower, but by about Ch. 26 you're flogging a dead horse. For a home in a high field strength area, a bit of poorly shielded coax might be pulling in more signal for the lower frequency muxes than the aerial itself.

View attachment 380719
credit to aerials & TV for their graph.

In all likelihood though, the aerial is probably one of those 'wideband high-gain' models. A Group W aerial. If that's right, then @Rodders53 is on the money about aerial and cable degradation.

Odd things can happen with aerial systems. If you rule out simple stuff such as a plug being partially connected, or a poorly shielded fly lead allowing the signal to get knocked out by RFI from a HDMI lead, or a badly-designed switch-mode power supply bleeding out RFI, then what's left is the more obscure issues such as notch filters. This is where something like a trapped cable or a corroded connection still works except for a narrow range of frequencies. If those happen to coincide with one of the muxes the property would normally receive, then sure, you could lose the mux on Ch. 37 and still get the others.

Most decent TVs have the option to look at signal condition as part of the tuning menu. How you get to it, and the depth of the level the tools go to varies from brand to brand. My Panasonic TV gives me signal strength and signal quality. There's a bit error display along with the network name (North West, in my case), and there's the frequency and the channel displayed. It's not as accurate as my meter, but certainly good enough for a bit of quick troubleshooting.

I'm on Winter Hill, too. It's about 30 miles due north. Ch.37 is on 602.00 MHz.

If you've doublechecked the simple stuff such as plugs being pushed in all the way, and looked for more obscure causes such some bit of coax sheath - the outer insulation - stretching enough that the inner core starts to disengage from the plug it's supposed to be attached to, then what's left is the stuff which you may or may not be able to do something about. Replacing the aerial and the coax is probably going to be the answer.

Lucid, you overwhelm me with your technical knowledge. However, although there is a lot to consider in your reply, I shall certainly study it carefully (after printing it), and see what I can put into effect. Thanks muchly, for taking the trouble to type all that out. And all for a know-nothing like me! One thing I must remark on, and it is the fact that none the contributors to this thread have made any response to what I said about the ONE-OFF restoration of the TalkingPictures + multiplex that occurred spontaneously several weeks ago (and its subsequent disappearance, the next time I re-tuned the channels).
L.L.

 

[foxhole]

You could get https://talkingpicturestv.co.uk/tptv-encore-faqs/ Online and stream it.

 

[Lucky Luke]

You could get https://talkingpicturestv.co.uk/tptv-encore-faqs/ Online and stream it.

I suppose many another could do that, foxhole. However, I don't have broadband (though I did use it for years at one time). My computer is "tethered" to my phone, and it serves my simple needs well enough, while saving a chunk of money every month. It's very slow, and not very reliable, where downloads of any kind or viewing videos are concerned. Thanks for the suggestion though.
L.L.

 

[Lucid]

When WRH was changed to group A (circa 2020?) there was a free aerial upgrade scheme that affected viewers could apply to... far, far fewer aerials were replaced than expected.

It's surprising the numbers of properties still using (or appearing to use) what looks like '80s era contract aerials. The boost in power post-DSO and the all-or-nothing nature of digital TV reception probably means if it ain't broke, don't fix it.

Loads of properties still have the old aerials up but switched to Sky or cable TV.

I've had (still have one) Panny TVs that showed post-AGC signal strength and post error correction Q (10/10 on both pre and post DSO when the power emitted increased tenfold from Tacolneston). Their more modern sets are a lot better at informative metering.

Yeah, measuring after the AGC and post corrections is cheating, isn't it.

 

[Lucid]

none the contributors to this thread have made any response to what I said about the ONE-OFF restoration of the TalkingPictures + multiplex that occurred spontaneously several weeks ago (and its subsequent disappearance, the next time I re-tuned the channels).
L.L.

That could be as simple as the 'dodgy connection' that works some times and not others. I had a call out a few months ago like that. Reception would come and go. After checking all the stuff at ground level I got on the roof. When I came to the aerial cable connection, the whole thing was loose. A couple of wiggles and it came away, the whole thing. The steel bolt fixing had rusted through.

I guess depending how the wind blew the aerial, sometimes it would make a connection and other times it wouldn't. A new aerial and downlead sorted the issue.

 

[Wayners]

If you have internet then use that with Freely for freeview and give up on aerial is another option.
I wouldn't spend any money on fixing cables ect if the the signal will be switched off in the next 10 years.