Good morning, Flying Pram,
I've made a few observations in respect of signal strength/quality on various satellite channels. The signal strength in all cases has been 100% but the quality varies - see below:
10788 V Quality 100% BBC E Mids
10817 V Quality 100% BBC Oxford
12523 H Quality 30-40% Daystar (Not my usual viewing)
11953 H Quality 70% BBC News
10847 V Quality 100% BBC HD
............and in non-Freesat mode:
12051 V Quality 70% CNN
12207 V Quality 90-100% Sky News
A couple of points which might help:
(1) The dish is just below the gutter of this bungalow, but the local topography is such that it has a good 'take-off' in the required direction. I examined the installation a little earlier and there was minor play in the LNB. Manipulation of the component varied the quality on BBC News by -10%.
(2) The LNB is about seven or eight years old. I remember a few years ago when the BBC shifted some or all of its channels to a different satellite within the Astra cluster, that they were lost and the only way of retrieving them was by selecting Ch 303 (Yes, Sky Comedy!) before selecting the required BBC channel. I think that this was a recognised 'work around'. The problem disappeared when I disposed of the Panasonic Digibox in favour of the Humax box.
(3) The 'No, or bad, signal' banner appears more frequently on the poorer quality streams. Eg: the Daystar picture was particularly prone to breaking up.
I hope that there is now something to go on and that I haven't muddied the waters still further!
Thanks,
N o t a