"Mike Kaliski" wrote in
:

....
Any protection is better than nothing,

.... unless it lulls you into a false sense of security ...

a spark gap (old automobile
spark plug) or small neon tube, a couple of back to back diodes and a
5 megohm or higher resistor across the diodes to provide a static
discharge path will do the job for pennies.

as most of these may.

I do recall taking an early (probably the first) Collins digitally tuned
receiver to a coast radio station for evaluation. It had inverse parallel
diodes across the RF amp input for protection of the FETs and was totally
unusable as when the on-site 500kHz transmitter was keyed up, it wiped
out all of the receivers (not just this one) with broadband noise. It
took a few minutes to realise what was causing ALL of the ROs to hear the
station callsign, not as a beat note, but as noise as if it was near to
where they were listening and just needed to be tuned in. Whilst the
Collins was connected to an antenna, it caused havoc, even if powered
off!

Beware of the effects of inverse parallel diodes across the antenna.

Owen