Guardian Telecom Inc.
Installation and Operation
Model AS12
Page 8
Unit Operation
Normal Operation
The AS12 detects amplifier failure by comparing logic input through the
absence of an output signal.
LED Indicators
When an amplifier goes into a fault condition, the corresponding amplifier
status indicator LED on the front of the AS12 illuminates.
See: Front Panel
drawing.
o
the upper LED illuminates to show a history of amplifier failure and stays
lit until the reset button is pressed.
o
the lower LED stays illuminated as long as the amplifier is in a fault
condition.
If the standby amplifier goes into a fault condition, the lower Standby LED
illuminates and the upper LED will record the history.
Standby Failure
If a problem is external to the amplifier when the primary amplifier fails the
standby amplifier will also fail.
Multiple Amplifier Failure
If more than one amplifier fails at the same time, the standby amplifier will
only replace the highest priority (the lowest numbered) amplifier.
Tip: Certain problems
external to an amplifier
on the paging zone(s)
may case the primary
amplifier to fail.
Reset LED History
After identifying and correcting an amplifier fault, press the reset button to
clear LED history indicators.
Setting VOX Threshold Adjustments
The VOX threshold adjustment is used to compare with the Logic VOX
input from a device such as DA388 or a TOA automatic Microphone
Mixer VOX logic output to determine the presence of a valid audio output
from the amplifier.
With a variable signal input to the DA388, raise the level until the VOX
logic signal is just activated.
Turn the VOX Threshold adjustment to minimum and the event LED will
be illuminated.
Adjust the Threshold level until the event LED extinguishes.
Repeat the process for all channels.
