In gusty winds, TV signals disappear and can only be restored by
powering the receiver off and on again. Or at least that's the only way
I've discovered so far to restore normal operation.
The setup is a little unusual: a satellite internet link (which
continues to work throughout the gusts, so dish pointing isn't the
issue), a DVB-S LNB offset by the appropriate amount so that it 'sees'
the Astra 2A-B-D satellites instead of the Europasat internet satellite
which the dish is aimed at, a dish motor so that I can look at other TV
satellites if I don't mind losing the internet connection, a
multiplexer on the roof to combine DAB, FM, terrestrial and satellite
signals, and a matching demultiplexer beside the receiver.
It all works perfectly if the wind isn't blowing, but gets into some
odd state where the TV signal goes from 90% signal strength and 73% signal
quality to near zero strength and zero quality after a variable number
of gusts.
The coax downlead for TV is about 20 metres long and has a
copper-coated steel inner and a foil and braid outer.
I used the best coax only for the internet connection, which might have
been a mistake.
I wish now that I'd used top quality solid copper coax instead of stuff
with a copper coated steel inner, which must be more prone to
electrolytic corrosion and may have a higher resistance.
In desperation I may try replacing/remaking all the 'F' type coax
connectors, though I'm not sure why a poor connection would give the
odd effects in question.
Does a dish motor automatically drive a dish back to the original
position if a gust moves it a fraction of a degree away?
That, happening repeatedly, might (I suppose) overload the power supply
from the receiver, or cause a sudden drop in voltage which could
confuse the TV LNB.
The dish, motor, and receiver are all Fortec Star, which work well
enough in simpler setups.
Has anyone had similar experiences?
--
Windmill,
Use t m i l l
J.R.R. Tolkien:- @ S c o t s h o m e . c o m
All that is gold does not glister / Not all who wander are lost