While we were on topic with monitoring SZ/P25 trunked system without affiliating. I was wondering if anyone has played around with capacity plus systems to accomplish the same thing?
In the Capacity Plus systems I manage here, the radio does not "affiliate". However, the radio does send repeater wakeup messages when powering on or changing channels/talkgroups. If you change the input frequencies, the radio will bonk with an out of range indicator until it can fully track the system (usually 3-5 seconds). I guess technically I am transmitting and interacting with the system, but unless system owners DF every wakeup message or sit outside your facility, the probability of intercept seems quite low.