My very thick coax was running true the living room to the shack and I
heard from time to time...tick... tick and my wife didn't know where it was
coming from...No storm was audible ..
Well it was.... little sparks jumping between the shield
and the inner conductor!
Also did see sparks jumping between the center of a PL259 connector
and the outside ring at other times!..
When I used to run a three-eighths-wave on 160m, tuned with an ex-
broadcast receiver air-spaced variable capacitor, I would hear similar clicking
noises when no obvious storm was present. This was caused by sparks
across the capacitor. For any non-earthed antenna (my LF one is earthed
through the matching transformer) I would advise using a bleed resistor of a
few hundred kilohms to earth just to avoid this static build-up.
Mike, G3XDV (IO91VT)