All police communication codes in MA
10-4: Message Received
Used to acknowledge that a message or transmission was received and understood.
10-5: Repeat
10-6: Standby
10-8: Call
10-9: Meet
10-10: Your Location?
10-11: Radio Test (R1 to R9)
10-14: Disregard Previous
10-16: Freq. Request
10-17: Fire Box # Request
10-19: Monitor Freq
10-90: Essential Radio Traffic
10-91: Use Scrambler
10-95: Unauthorized Radio User
10-97: Hold Radio Traffic
10-99: Restrict Talk To Current Incident