P
AGE
14
of 28
A
UXILIARY
P
OWERED
ADA-C
OMPLIANT
E
MERGENCY
P
HONES
Pub.
42004-378A
d:\standard ioms - current release\42004 instr. manuals\42004-378a.doc
05/06
Audio Level Adjustments
Speaker Volume Adjustments
The speaker volume and microphone sensitivity are factory set to nominal levels that are acceptable for
most installations. However, some installations may require adjustments for the speaker and microphone.
Both the speaker and microphone adjustments are made using potentiometers on the emergency phone
PCBA. R106 is the speaker volume adjustment, and R88 is the microphone sensitivity adjustment.
Please refer to Figure 13 for the potentiometer locations.
Special care must be given to adjusting the speaker volume and microphone level. If one or both of the
levels are set too high, acoustic feedback (howling) can occur. If acoustic feedback occurs, we
recommend returning both potentiometers to the nominal factory settings and beginning the adjustment
again from this point.
Additionally, the acoustical characteristics of the emergency phones are different both when the front
panel is removed from the enclosure and when the front panel is tightly mounted in the enclosure. After
making any volume adjustments, we recommend mounting the front panel to the enclosure and again
testing the phone.