1. Siren or alarm switch
2. Power LED indicator
3. General switch
4. 6.3 mm input for microphone 1
5. Gain control for microphone 1
6. 6.3 mm input for microphone 2
7. Gain control for microphone 2
8. 6.3 mm auxiliary input
9. Gain control for auxiliary
10. Slot for SD memory
11. Slot for USB memory (Only in AMP-120SD)
12. Play / Pause
13. Change of mode
14. No function
15. Display
16. IR sensor
17. Physical volume control of the player
18. Equalizer / Repeat Track
19. On / Off switch for the MP3 player
20. Next track / Increase virtual volume
21. Previous track / Decrease virtual volume
3
22. Stop track
23. COM, 4, 8 and 16 Ω impedance outputs
24. Line outputs 70 and 100 V
25. Terminals for 12 V battery - - - 10 A
26. GND connection
27. Fuse compartment
28. Input for interlock cable