If a bit of rain is enough to lose the signal then something in your installation is marginal. A dish mounting that is not secure enough and has shifted, an LNB on its' way out, or water getting into the feeder cable would be the first things I'd look for.
That seems to be a common one, esp after the winds we had last week. It seems many of our friendly, subcontracted Sky installers haven't been given spanners (or ladders, come to that) by Uncle Rupert. Or maybe all Sky employees are have the strength of The Useless Student 
(although, in Tunnie's defence, even he could mount the bloody dishes higher without a ladder).
Chatting to an installer other day, amount of Health & Saftey crap they have to do before going up a ladder is insane. Takes longer to go through that, than actually putting up the dish!
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As Mark (tunnie) is aware, my recent Sky instal was done by Sub Contractors & after they came back to rip out the initial Dogs Dinner & do it again I was left with 12 anchor bolt holes in my rear walls, 4 of which were for 'Safety Hooks' to attach the ladder! The first dish instal was at just above head height on my single storey kitchen extension wall, the second was just under my bathroom window approx 50cm above the flat kitchen roof & the cables were fixed at 1.5 metres above the flat roof. They then ran the cables along the side of the house at a height above ground level of 4 metres entailing a further 7 'Safety Hook' holes, but thankfully no further holes in the front of the house as they laid the cables along the top of the front door canopy & then clipped them to the wooden bay window. I almost lost my Rag with the boss of the subby firm when I queried the number of holes & he spouted all this verbal bullsh*te about H&S and said Sky insisted on applying it to the final letter & full stop!! Four days later we had the high winds mentioned earlier & lost the signal! On checking, I found the dish had moved, probably due to only being fixed by one nut & bolt on the adjustable bracket

Another 3 days later a 'proper' Sky installer came out and refixed the dish higher up the wall as he said it was too low & reception would be lost in the Spring when neighbouring trees resprouted and although it needed
another 4 holes to fix the dish he refrained from drilling yet another few safety holes. So now I have an acceptable installation but my house resembles a Swiss Cheese!

This Health & Safety nonsense is just that,
nonsense as the Legislation is misinterpreted to suit the individual circumstance to make life easier for the worker & bugger Joe Public! Common Sense is nowhere to be seen anymore it would seem.
