My ITV/C4 Freeview channels have disappeared - what can I do? Is it my SCART ca
It is a feature of television signals that they can be effected by the weather. Aside from the obvious damaged that can be caused by wind or torrential rain, the onset of summer can cause a more intriguing problem called "inversion".
Basically, when the sun heats up the land, the hot air can get trapped below cold air at high level. This creates an "inversion layer" which acts like a polished mirror to TV signals. This causes two problems: you can receive both the original and a reflected signal from your own transmitter (on analogue TV this appears as "ghosting") or interference from TV transmitters that are normally too far distant.
The ITV/C4 multiplex of channels (ITV-1, ITV-2, ITV-3, ITV-4, CITV, C4, More4, E4, Quizcall) use a transmission "mode" called 64QAM, and it is sadly much more prone to these problems.
So, whilst a loft-mounted aerial will provide reception at some time, it will fail at others. The only real solution is to mount the aerial (or a new Class I aerial) outside on a pole, but some people report that changing the cable from the aerial to the set-top box to the high-grade satellite cable can also help.
The SCART connection, by the way, only carries a single TV picture, not the Freeview transmission multiplexes, so if this is disconnected it will result in degradation to every channel at once.
Daniel McCormick: Most likely because of either interference or a fault with your aerial system. As you haven't said where you are (please provide a full postcode) or which transmitter you're using, we can't check for any reported faults or engineering work.
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Without a full postcode we haven't a clue which transmitter(s) you may be able to get your signals from, there are over 1100 in the UK. Transmitters undergo periodic maintenance (Planned Engineering) and occasionally develop faults and not knowing which transmitter is affecting you, we can't advise.
In any event interruptions are not normally that long, you signals may well be back by now.
Do NOT retune whilst you have no signal, it usually just clears your correct tuning and you'll have to try retuning again, maybe several times as you won't know when the signals are back!
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