Itv , Channel 5 And 6 On The Blink.

[DTCwordfan]

These three channels have suddenly become weaker here and now disappeared from the TV as to signal. Have tried reprogramming to no avail.

Are there any TV comms specialists who may know what is causing this and how to rectify the situation?

The area is around C Cornwall.........

Thanks in advance (out for lunch but will respond later).

[Svejk]

I'm surprised at you,DTC. Watching crap channels like them. ;)

[Chillum]

This may help, it may not...but it's worth a go for anyone who seems to have "lost" some channels, and an autotune doesn't restore them..
1. Unplug your aerial from the television (or set-top box if you use one).
2. Use the autotune function of your television to re-scan for available channels.
Obviously it will find NO channels because you have unplugged the aerial.
3. Plug the aerial back in and once again re-scan using the autotune function.
The "missing" channels should (with any luck) be restored.
I don't pretend to know why this works, but it is apparently as near to a "reset" as you can get with Freeview.
I hope it works for you.

[SeaJayPea]

Bet there's some transmitter work going on and that it'll be back tomorrow. Try checking with a neighbour to see if they're having the same problem.

[DTCwordfan]

Thanks all - Chillum, I will have a go at that later. SeajayPea, a good suggestion limited by the fact that there are few neighbours. Svejk, not all C5 is bad, you know, and then there is the question of the Mater when I am not here.....

[Svejk]

To be honest I'm judge Judy's biggest fan. I only said that to 'bump' you back up the board. And provoke an argument, of course.;)

[Buenchico]

>>>Are there any TV comms specialists who may know what is causing this

Freeview channels are transmitted in 'bundles' (called 'multiplexes') with each multiplex using a different channel. Theoretically you should a different aerial on your roof for each multiplex because the elements of each aerial should be exactly the right length to 'resonate' with the incoming frequency that it's designed to receive.

Obviously having dozens of aerials on your roof is impractical, so we all use aerials that are only a 'rough match' to each of the frequencies. That inevitably means that any particular aerial will be better at receiving some multiplexes than others. (Yours clearly resonates poorly with the frequency used by the multiplex containing the missing channels).

The strength of signals received by your TV aerial don't remain constant. They're affected by atmospheric pressure, weather conditions, the 11-year sunspot cycle, individual flares on the surface of the sun, interference from other radio transmitters, interference from your own electrical equipment (such as TVs, computers, monitors, printers, etc), interference from your neighbours' electrical equipment, and many other things. Your aerial is good enough to 'pull in' signals from the relevant multiplex when conditions are good but can't cope when conditions are poor.

>>>and how to rectify the situation?

Theoretically you should be considering replacing your TV aerial (and its associated cabling) but, in practice, a signal booster will almost certainly solve the problem. Most large supermarkets (such as Tesco and Asda) sell them for around a tenner but this model, from Maplin, offers more 'gain':
http://www.maplin.co.uk/1-way-aerial-amplifier-223504

[Buenchico]

Typo!

Line 4, above, should have read:
"with each multiplex using a different frequency"

[netibiza]

When you unplug the aerial, do you mean Sky, as I also have Spanish and that would be a begger to get back. Just thought if I do that it'll just retune the Spanish channels.

[modeller]

All the channels I mentioned appear under ' listing' and guide.
The the signal strength for the Freescan box is showing maximum.
Yesterday RT has now disappeared from the listing. The others Al Jezeera and Euro news are listed but there is NO SIGNAL .
I can get them on another TV using Freeview. but not on my main TV using Freescan.

[modeller]

Over the past two weeks several channels have gone missing on Freesat but should be back to normal today 11 Oct 13. However if it hasn't retuned automatically you must do an initial retune . See it in Menu under settings.