In article , "Ryan, KC8PMX"
writes:

Yes, it is vandalism, but a simple needle or pin placed directly in the coax
usually does the trick from what I hear. Or take some wire cutters, and
clip the wire, connect the shielding and center conductor of the coax
together and tape both ends back together with black electrical tape would
do the trick as well. Granted, not legal and probably not ethical either,
but the techniques would work in making it a little "quieter."

No need to get fancy on that. For the PL-259 "UHF" type connector,
just do one winding of transparent tape around the male pin. Gives it a
hard-to-see insulator when mated. [old Signal School trick...:-) ]

LHA