AA-100/AA-120 Audio Amplifiers 5. Voice Alarm Systems
Unimode 400 Operations PN 50709:A 10/20/97 37
AA-100/AA-120 Audio Amplifiers
Figure 37 shows the AA-100/AA-120 circuit board and identifies key components:
Figure 37 AA-100/AA-120 Circuit Board
Table 33 AA-100/AA-120 Indicators
Notes:
1. During complete loss of primary (AC) power, the AA-100/AA-120 operates on
secondary (battery) power. To conserve secondary power, no LEDs light on the
AA-100/AA-120 while operating on batteries.
2. An audio amplifier does not indicate a trouble condition until 40 seconds after a
fault occurs.
3. To calibrate audio amplifiers, install a 470-ohm resistor at the end of the low-level
audio circuit. If the low-level audio circuit is configured as four wire circuit, install
a 470-ohm resistor at the point furthest from the AMG-1 or ATG-2.
LED Lights when...
Normal Level The audio amplifier is adjusted properly and operating correctly
during normal (non-alarm) conditions.
Incorrect Level The audio amplifier is out of adjustment during normal (non-alarm)
conditions.
Battery Trouble The battery voltage is below a sufficient level.
Brownout The AC power source is below a sufficient level. During a complete
loss of AC power, no LEDs will light on the AA-100/AA-120.
Speaker Trouble An open circuit condition occurs in the four-wire, high-level output.
Input Trouble A loss of the low-level audio input signal, or an amplifier failure.
(see note below)
Amplifier Trouble A loss of the low-level audio input signal, or an amplifier failure.
(see note 3 below)
Normal Level LED
Incorrect Level LED
Battery Trouble LED
Brownout LED
Speaker Trouble LED
Input Trouble LED
Amplifier Trouble LED
Audio Gain Rotary Switch (Refer to “Adjusting
the Audio Gain Level (AA-30, AA-100/AA-
120)” on page 38)
SW1 – Backup tone (Refer to “Selecting the
AA-100/AA-120 Backup Tone” on page 38)