I recently began to monitor the old vhf-lo freq 42.8200 which was used by the Roseburg OSP office in years past. I noticed it popped up during one of my searches. It has intermittent tones which sound like data bursts. Some transmissions are stronger than others suggesting several transmitters. Does anyone know what they are using this vhf-lo freq for and/or heard the same thing on this or other lo band freq.'s. - Thanks
Skip or Tropospheric Ducting from far away is a possible explanation,
UNLESS you hear the transmissions regularly
and with approximately
the same signal levels.
There have been some very brief openings lately.
put all of the 39, 42, 44 & 47 MHz frequencies allocated to Public Safety
into a bank or two and scan them. If you hear activity on maybe several over a brief time period,
then later (the majority of the time) they're silent, it's undoubtedly the case.
Probably tropo from CA, because skip's lousy now, but who knows.
When the skip was in heavy, quite a few years ago, I'd copy fire tap-outs,
from dispatchers with heavy east coast accents giving eastern time
and then their call signs which I identified in the FCC database.
Also, around the same time, I copied Maryland State Patrol giving a BOLO
for a car heading toward Washington, DC