We used software that will tell you several things called Clone Watch from Genesis:
Read all about it here:
CloneWatch
Some features (not all inclusive):
1. invalid radio ID's,
2. duplicate radio ID's
3. radio ID's on talkgroups not authorized.
The invalid one's were easy. You use a radio ID not authorized on the system. You affiliate, you get zapped.
The duplicate ID...sometimes people will program radios using the same ID as a valid user. The software would show two ID's on the system at the same time usually on different sites. Once we figure out the good one, we call that radio in and issue it a new ID and zap the duplicate. What alot of people don't realize is by using the same ID, you can actually force the good ID off his site making that radio unable to transmit and call for help. Very dangerous.
Talkgroups not authorized,..Fire/Rescue guy decided he wanted to listen to the Sheriff's Tac channel on his portable. So he took his radio to someone with CPS and "some" knowledge and added the talkgroup. He sent his radio into the shop when it went dead on him. He gave up the guy who programmed his radio when his job and criminal charges were on the line.
What amazes me is the entire system was in the clear, unencrypted. Anyone with a scanner could hear everything on the system.
I'm dating myself but I've even bricked a few radios using MDC-1200 on an analog repeater!