Can't view HD channels

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Discussion

taxboy

Original Poster:

262 posts

205 months

Wednesday 16th November 2022
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Just wondering if there are any TV gurus who could help please. I've got a Sony XF9005 and I've lost all my HD channels. I've tried an auto retune and also a reboot of the TV but with no luck.

Ive checked the Freeview website and it shows no issues with the Talconeston transmitter so suggestions for next steps please

TheInternet

4,929 posts

170 months

Wednesday 16th November 2022
quotequote all
When was it last there? Can you see 5SELECT on channel 56? Does the TV have a signal strength indicator buried somewhere?

taxboy

Original Poster:

262 posts

205 months

Wednesday 16th November 2022
quotequote all
TheInternet said:
When was it last there? Can you see 5SELECT on channel 56? Does the TV have a signal strength indicator buried somewhere?
Probably a couple of weeks ago. No I can't see Channel 56

Finally found the signal menu !! Strength 100 quality 18/100

Miserablegit

4,173 posts

116 months

Wednesday 16th November 2022
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I think they’ve all gone
I don’t watch much live tv but when I tried to a few weeks ago, like you, I couldn’t find any HD channels- I understand they have been cancelled to free up frequencies for 5g.

TheInternet

4,929 posts

170 months

Wednesday 16th November 2022
quotequote all
Miserablegit said:
I think they’ve all gone
Nope

Mr Pointy

11,853 posts

166 months

Wednesday 16th November 2022
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It looks like you've lost the highest frequency Mux (BBC B) on channel 46. It's often an indication of a antenna or cable fault so you might want to get the cable run checked. Given that it's started recently it could be water in the join or cable.

Badda

2,901 posts

89 months

Wednesday 16th November 2022
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Miserablegit said:
I think they’ve all gone
I don’t watch much live tv but when I tried to a few weeks ago, like you, I couldn’t find any HD channels- I understand they have been cancelled to free up frequencies for 5g.
No this isn’t true.

ReallyReallyGood

1,632 posts

137 months

Wednesday 16th November 2022
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Weather related?

Miserablegit

4,173 posts

116 months

Thursday 17th November 2022
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Apologies for duff info - I’m now able to get BBC1 HD again on 101 - haven’t been able to for weeks.
Seems it was only BBC News HD that was cut
Thanks all!

taxboy

Original Poster:

262 posts

205 months

Thursday 17th November 2022
quotequote all
Mr Pointy said:
It looks like you've lost the highest frequency Mux (BBC B) on channel 46. It's often an indication of a antenna or cable fault so you might want to get the cable run checked. Given that it's started recently it could be water in the join or cable.
Thanks for that I'll get someone out to check it. Just wanted to make certain it wasn't something I was doing

dickymint

25,854 posts

265 months

Friday 18th November 2022
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Are you watching direct from TV or through a BT Box or similar?

taxboy

Original Poster:

262 posts

205 months

Friday 18th November 2022
quotequote all
dickymint said:
Are you watching direct from TV or through a BT Box or similar?
Direct from a TV via an external aerial

taxboy

Original Poster:

262 posts

205 months

Friday 18th November 2022
quotequote all
EmailAddress said:
Presumably you've gone through the obvious...

https://www.freeview.co.uk/help/reception-picture-...
Yup and also my neighbour is receiving the HD channels so it sounds like an aerial/cable issue

I'll post the solution in case anyone experiences similar in the future

indigochim

1,671 posts

137 months

Friday 18th November 2022
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The Inlaws had an issue with channels a while back. They oddly had too strong a signal which I think may have been caused by the aerial 1st going to a recorder and then on to the TV. The answer for them was to fit an inline attenuator which solved their issue. No idea if you could have the same problem.

Lucid_AV

441 posts

43 months

Friday 18th November 2022
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taxboy said:
Probably a couple of weeks ago. No I can't see Channel 56

Finally found the signal menu !! Strength 100 quality 18/100
Strength maxed out (100) but Quality low suggests over-amplification. Do you have a masthead amplified splitter somewhere?

The TV signal metering isn't dead-on accurate. On the Pana in my lounge it will read 100 for strength at anything over about 50dBu. It doesn't differentiate between 50dBu (which is acceptable) and 70dBu where it's over the recommended threshold. The TV is still happy with the Strength, but if the signal gets any more amplification then the Quality will start to nosedive.

The recommended levels for Strength are 45-65dBu. Not all TVs are as forgiving of over-amplification.

Quality is the measure of signal to noise. (There's a bit more to it than that, but this description will do for now.) When an amplifier is added between the aerial and the TV then it boosts Strength but adds noise and so makes the signal to noise ratio worse. The more the amplification then the worse the S/N.



taxboy

Original Poster:

262 posts

205 months

Friday 18th November 2022
quotequote all
Lucid_AV said:
Strength maxed out (100) but Quality low suggests over-amplification. Do you have a masthead amplified splitter somewhere?

The TV signal metering isn't dead-on accurate. On the Pana in my lounge it will read 100 for strength at anything over about 50dBu. It doesn't differentiate between 50dBu (which is acceptable) and 70dBu where it's over the recommended threshold. The TV is still happy with the Strength, but if the signal gets any more amplification then the Quality will start to nosedive.

The recommended levels for Strength are 45-65dBu. Not all TVs are as forgiving of over-amplification.

Quality is the measure of signal to noise. (There's a bit more to it than that, but this description will do for now.) When an amplifier is added between the aerial and the TV then it boosts Strength but adds noise and so makes the signal to noise ratio worse. The more the amplification then the worse the S/N.
Thanks for that. I was vaguely aware of too much amplification. Im assuming it's not that as it's been fine until now

taxboy

Original Poster:

262 posts

205 months

Monday 21st November 2022
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All sorted now !! I needed a new amp box - apparently the existing one was quite old

taxboy

Original Poster:

262 posts

205 months

Monday 21st November 2022
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EmailAddress said:
'Amplifier' box?

Any recommendations as we could do with one too.
The one the guy fitted is a Wolsey if that helps. He explained the new boxes aren't powered in the loft any more to avoid potential fire risk, so the new one is sitting behind the TV - more cabling !!

taxboy

Original Poster:

262 posts

205 months

Monday 21st November 2022
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It's still plugged in to the mains but apparently sends a low voltage back up to the aerial. I think he said he'd set mine up for a 10db gain if that helps

Mr Pointy

11,853 posts

166 months

Monday 21st November 2022
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EmailAddress said:
I can't quite wrap my head around how the non-powered versions work.

We've been looking at the Wolsey. Let us know what your gains are and all that biggrin

Glad you got it sorted.
Many TVs & Recorders have the facilty to feed a low voltage (usually 12V) back up the cable to power the amplifier. This site has a lot of information:
https://www.aerialsandtv.com/knowledge
https://www.aerialsandtv.com/online-shop