P
UB
.
42004-352K
ADA-C
OMPLIANT
E
MERGENCY
P
HONES
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AGE
14
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d:\standard ioms - current release\42004 instr. manuals\42004-352k.doc
06/06
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.
After making any adjustments to the audio levels, perform the automatic line level compensation as
detailed below.
When the phones leave the factory, the microphone potentiometer is set near minimum, and the speaker
pot is set to maximum. The speaker volume potentiometer (R106) provides a 6-dB range of adjustment
and the microphone sensitivity potentiometer (R88) provides a 12-dB range of adjustment.
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 phone with the front panel removed are
different than 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 testing the phone again.
Automatic Line Level Compensation for Optimum Audio Performance
Every telephone line has different audio and electrical characteristics. To accommodate the varying lines,
the telephone has an automatic line level compensation function. When a telephone is first installed and
connected to a telephone line, we recommend resetting the automatic level compensation feature. The
automatic line level compensation feature is reset remotely (See the Remote Programming Section of this
manual) or locally with the
#2316
command, as follows:
For single button emergency phones:
1.
Remove the phone from the back box or enclosure.
2.
Disconnect the
E
MERGENCY
push button from
J7
, the “Emerg PB” socket on the phone PCBA.
3.
Connect the
E
MERGENCY
push button to
J1
, the “Call PB” socket on the phone PCBA.
4.
On the PCBA, enable auto-answer by placing a jumper between pins 2 and 3 on
J14
and disable
password protection by removing the jumper from
J9
.
5.
Connect a keypad to
J13
. (Keypad, Part No. 51035-011, and Keypad Cable Assembly, Part No.
61504-048 are sold separately).
6.
Press the
E
MERGENCY
button. After you hear the dial tone, simultaneously press the
1
and
#
keys.
After a confirmation tone is heard, enter the command
#2316
. To hang up the phone, press the
E
MERGENCY
button or wait for the phone to time out.
7.
Press the
E
MERGENCY
push button.
When dial tone is steady (with no volume variations), the process is complete. Depending on the
phone line and the duration dial tone, it may be necessary to repeat this step one or more times.
