We had a pager spur problem with our repeater (no pl). The problem would
come and go. We determined it happened mostly with time of day (outside
temperature). Sometime it was just a short 1 second event and sometimes it
would hold for a bit more (maybe 2 -5 sec). We setup a satellite multimode
radio (actually dial in the frequency with widest bandwidth setting) and
monitored the repeater input with a tape recorder and vox. We did this to
capture the audio so we could listen to characteristics and THE CW CALLSIGN.
We captured enough of the callsign that we were able to indentify the whole
call (and freq) from the FCC database.
With that, we were able to monitor the repeater and the pager for hits. Yes,
it did hit some times and not others. The reason was, it was caused by an
unstable spur that drifted up and down the ham band with temperature and the
amount of pager traffic. It was also hitting other repeaters as it drifted
but most of the other repeaters had pl.
There was a chain of pagers using the same freq and callsign and we had to
figure out which tower it was. We used a beam antenna and chased the spur
up/down the band until we were able to get a definite direction. The next
step as to visit the site AREA with an HT and just scan the ham repeater
input freqs during the likely time of day. Bingo, the spur was loud and
clear!.
Of course the pager owner was in denial but being a pest for a couple of
weeks got the problem removed. They claim it was a spur in the final PA that
had been serviced just at the time the problem started. They replaced the
PA.
Hope this story helps.
Tom