GAI-Tronics 701-312 Handset/Speaker Amplifier - Manual (Page 3)

Pub. 42004-319
Model 701-312 Page/Party
®
600-Ohm Handset/Speaker Amplifier Page: 3 of 5
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Maintenance
Adjustments
Four adjustments are accessible through the rear chassis of the amplifier using a small standard
screwdriver. Each adjustment is clearly labeled. The adjustments have been factory-set for optimal
performance. Do not adjust these levels unless you have followed all the steps in the Troubleshooting
section and are still not satisfied with the station performance.
• Microphone Gain: adjusts the gain level from the microphone signal to the page or party lines
• Receiver Sidetone: the amount of signal transmitted from the microphone to the receiver of a handset
• Receiver Volume: adjusts the gain level from a party line to the receiver
• Speaker Amplifier Gain: adjusts the speaker volume (also accessible from the front panel)
Troubleshooting
The following table lists some difficulties encountered in Page/Party
®
systems. Included are some
troubleshooting hints to aid in remedying these problems.
Problem Solution
Any problem with station
performance occurs. Review the steps of the installation, ensuring that you have correctly
followed ALL steps. Check all the terminations in the amplifier
enclosure and in the line balance assembly before proceeding to any
other adjustments.
Verify the system’s line balance assembly is a Model 305-002 or that the
existing line balance is set for 600-ohm operation.
Speaker level requires
adjustment. 1. Adjust the volume control behind the nameplate on the front panel.
2. Replace the speaker or driver.
Outgoing conversation level
requires adjustment. 1. Adjust the microphone gain by removing the amplifier from the
amplifier enclosure and attaching a Model 10440 Series extension
cable between the connectors. Use a small standard screwdriver
(
1 /
8-
inch blade) to slowly turn potentiometer (R17) on the rear
chassis of amplifier until reaching the proper microphone gain.
2. Replace the handset microphone.
Incoming conversation level
requires adjustment. 1. Use a small standard screwdriver to adjust the receiver volume
control on the rear of the amplifier using the Model 10440 Series
extension cable as described above.
2. Replace the receiver element in the handset.
Feedback/distortion (a hum or
buzz on the line) occurs during
all Page/Party
®
station
operation.
1. Adjust the receiver sidetone on the rear of the amplifier using the
ribbon cable assembly as described above.
2. The line may be improperly terminated. Inspect the system cable for
loose connections, shorts, and grounds. Line balance assembly
connections are critical.