ACS 775SL-100 Operations and Installation Manual
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Front Panel Controls
Operation
Front Panels Controls
Description
The ACS 775SL-100 Single Audio Mixer Panel is a compact, lightweight unit which provides full audio
control for a single position in the aircraft. It has the capability to provide its user with 4 receive audio
selections, 5 transmitter selections, and full headphone audio and ICS volume control.
1 - NORM - EMER Switch
This switch controls the operation of the audio panel in the event of an audio amplifier failure. In the
“up” position (NORM) the audio panel is in normal operating mode. In the “down” position (EMER) all
audios are summed and then fed directly to the headphones. This enables the use of the transmitters
and other equipment during audio amplifier failure.
2 - Receive Audio Select-Mute Switches
Normal operation - In the “up” position the audio selected is channeled to its proper headphone. In the
“down” position the audio selected is muted.
Emergency operation - In the “up” position the audio selected is muted. In the"down" position the audio
selected is summed with any other audios selected and then sent to the headphone.
3 - Headphone Volume Controls
Clockwise rotation increases the volume - counter clockwise rotation decreases the headphone volume.
In the event of excessive or inadequate receiver volume the pots located on the rear of the unit may be
adjusted for the proper level. (see FIGURE 2)
4 - Lighting
The audio panel is lit by two 14V (P/N 330) lamps which provide night time visibility for all panel legends.
These lamps may be replaced in the event of a failure by unscrewing the front panel mounted filter cap,
inserting a new lamp, and reinserting the filter into the front panel.
5 - Mic Selector
This rotary switch performs three functions simultaneously. It (a) connects the mic to the selected
transmitter (b) selects the associated keyline, and (c) selects the associated audio (if not already
selected using the audio select-mute switch).
6 - Transmit Indicator
When the transmit key is activated this indicator lights up showing that the audio panel is in the transmit
mode.
See Figure 1
