In message
-septemb
er.org, Tim writes

I would hazard a guess that the likeliest cause is a poor connection in the
plug that's that's going to the amp. I'd take it apart and make sure that
the screen isn't shorting with the central conductor.

Tim


Another favourite problem is pin of the plug, assuming a Belling Lee
plug rather than an F. Quite often for speed the installer will not
solder the coax inner to the pin of the plug, maybe he will have crudely
crimped it with a pair of side cutters, most likely not though. This
can lead to problems years down the line with corrosion isolating the
coax inner from the pin. Any slight movement could have remade the
connection. Although the pin and inner may not have been making contact
there could have been enough capacitance for a signal to get across, but
not strong enough to give a good picture.
--
Bill