A1- A2: Master output auxiliary controls to electronically balanced outputs.

AFL: After Fade Listen of auxiliaries on PFL monitors.

Ex 1-SUB: Left and Right source select Touch Buttons to control-room monitors. Electronically interlocked, current button disables previous.

LOUDSPEAKER VOLUME

MUTE: Mutes control-room loudspeaker, can be jumper select to dim @ -20dB. Mute LED on if control-room microphone is active.
PFL: Select Pre Fade Listen to loudspeaker.

HEADPHONES VOLUME

SPLIT: Allows simultaneous monitoring on head-phones of selected signal and PFL.

LOCAL: Overrides module control of Time

DUMP: Use with DELAY unit.

+17v. -17v. +48v. +5v.: Power supply status.

OSC ON: Activates internal Oscillator @ 1kHz.
Can be disabled in ACCEPT mode.

REF LEVEL: Set oscillator level ±10dB internal and external.

PGM. AUD. SUB: Assigns oscillator to busses.
10kHz: Select 10kHz internal oscillator.

Ex 1- SUB: Left and Right source select Touch 
Buttons to studio monitors. Electronic Interlock.

LOUDSPEAKER VOLUME

MUTE: Mutes studio loudspeaker. Mute LED on if studio microphones are active.

HEADPHONES VOLUME

TALK-BACK: Built-in electret microphone with master level control. Also used with C203 Telephone module.
REMOTE button to select external Microphone.

EXT: Assignable with logic to one External destination with reverse communication and level adjust.

A1- A2: Assign to auxiliary busses. 
ST: Assign to studio loudspeakers and phones.

PHONES: Connected to control-room stereo output. Load 8 to 2000 ohm