GAI-Tronics Call/Talk Installation of Call/Talk Systems - Manual (Page 3)

Pub. 42004-251A
Installation of Call/Talk Systems Page: 3 of 9
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STEP 4 - Amplifier and Subset Installation
Call/Talk equipment is factory set for automatic local speaker muting. When the push-to-page switch is
pressed at a particular station, the paging speaker connected to that station is silenced, preventing acoustic
feedback to the handset microphone. For cases where the muting feature is not necessary or may be a
disadvantage, it can be disconnected by removing the jumper between the MUTE IN and the MUTE OUT
terminals.
Remote Muting
Additional amplifiers can be muted by the paging station by connecting its MUTE OUT terminal to the
MUTE IN terminal of all affected amplifiers. This can be performed to avoid feedback from stations in
proximity of each other. A common ground must be present at all stations to be muted. Connect one end
of the GAI-Tronics orange cable wire to the MUTE IN of one station, and connect the other end to the
MUTE OUT of another station. Continue this procedure until all stations in that area are connected. To
ensure that the stations are correctly wired, initiate a page from a station, and verify that speaker muting is
occurring where desired.
After making any necessary muting changes, unpack and install the C01B power supply and the D01B
speaker amplifier. The C01B and the D01B modules plug directly into the motherboard located in the
station enclosure. Secure the module to the enclosure mounting bracket using the captive screws provided
with the modules. The ribbon cable from the front panel containing the handset amplifier plugs into the
mating connector on the motherboard. The cover plate should also be plug-connected to the motherboard
and securely mounted to the enclosure using the hardware provided.
Step 5 - Checkout and Adjustment
All field wiring connections (page line, party line(s), mute, ac power, and speaker) between stations must
be tested, and the line balance assembly installation must be complete before checkout begins. Every
handset should be on-hook.
Apply the ac power, and check the station next to the line balance assembly. Press the push-to-page switch
(in the handset handle on some stations), and speak firmly and directly into the microphone of the handset.
The broadcast should be heard at all paging speakers in the system except those associated with the station
under test. The operator should hear little or no sidetone (the user hearing his voice from the earpiece of
the handset). If the line balance assembly is not connected properly, there will be a high level of sidetone,
perhaps enough to cause feedback. The line balance assembly adjusts to optimize sidetone rejection on the
page line. If the system is complete when the first station is checked, adjust the line balance assembly as
presented in the Line Balance Assembly Adjustment section below. Do NOT adjust the station (amplifier)
controls until the line balance assembly is adjusted.
Release the push-to-page switch, and check the party line(s) sidetone level. Again, the operator speaking
into the microphone of the handset should hear very little or none of his own voice from the earpiece in the
handset. This sidetone rejection will only occur if the line balance assembly is properly connected, because
it contains a fixed resistor load for each party line. In addition, no party line adjustments are provided;
therefore, party line operation is checked by conversing between two or more stations.