Morse code is used to ID the transmitter, and that is permitted. Anyone with a decent rooftop antenna in the Philly area can hear a similar ID on the national police channel (155.475) coming out of I think Berks County.
Correct on Berks 155.475. Every 25 min or so. Good beacon signal.
much slower morse ID's heard on these: The UCALL is slamming signal, I believe it is a link I/O of the Closed Sky system.
Nothing on not on the 7CALL's though.