CRT SS 7900 User Manual page 12

Rear Panel
No. Functions
19 External SP Jack
20 External PA Jack
21 Antenna Jack
22 Power Supply Jack
Microphone
Channel Down
PTT button
RJ45 connector
21 20
ANT.
PA.SP.
POWER +
6
19
EXT.SP.
22
Channel UP
Mic
Microphone cable