2820A-02 & 2820A-03 CHAMBER COMMUNICATOR USER MANUAL
2820A-02-UM
REV 1.0
22
To troubleshoot acoustic feedback issues first determine the source. One way to quickly
determine the source of the acoustic feedback is to cover each active microphone with your
hand, one at a time. Another method is to adjust the volume controls one at a time. The
volume control that stops the feedback indicates the source. For example if the OUTER
LOCK VOLUME control stops the feedback, then the problem is likely in the headset located
in the outer lock. Common sources are feedback between the operator’s headset microphone
and the PANEL SPEAKER. If the operator wants to operate with the headset and leave the
PANEL SPEAKER on, Amron recommends the tender move away from the unit by using the
Amron Model 2822-28 Remote Walk-and-Talk Module. This module provides an "extension"
cord for the tender headset.
Crosstalk is caused by signal leakage between the microphone and earphone wires in the
chamber wiring. In a good cable with all the wires open (not connected), the resistance
between any two wires should be greater than 10 Meg-Ohms. Over time, the cable can be
damaged and this resistance drops to the point that crosstalk can occur. When this occurs,
the chamber communication wiring should be replaced. Amron strongly recommends the use
of the twisted, shielded wire pairs for all communication cables to prevent cable crosstalk.
PUSH-TO-TALK DOES NOT WORK
If used, check the connection to the handheld microphone. A common issue is that the yellow
banana plug is not properly seated in the PUSH-TO-TALK JACK. If the tender is using the
PANEL SPEAKER as the microphone with the PUSH-TO-TALK BUTTON, make sure the
SPEAKER SWITCH is turned on. If neither of these solves the problem, there could be a
broken wire inside the diver communicator. Open the front panel and inspect as described in
section 4.6. If that does not resolve the problem then contact Amron for further assistance.
7.9
PUSH-TO-TALK DOES NOT WORK
If used, check the connection to the handheld microphone. A common issue is that the yellow
banana plug is not properly seated in the PUSH-TO-TALK JACK. If the operator is using the
PANEL MIC with the PUSH-TO-TALK SWITCH, make sure the SPEAKER SWITCH is turned
on. If neither of these solves the problem, there could be a broken wire inside the chamber
communicator. Open the front panel and inspect as described in section 4.6. If that does not
resolve the problem then contact Amron for further assistance.
8 DRAWINGS
The following drawings illustrate the electrical and mechanical details of the diver communication
unit. The corresponding parts lists for each drawing are detailed in the parts lists section, or are
included as part of the drawing. All drawings are at their current revision level as of the date of
printing. Amron reserves the rights to revise the documentation without notification.
Summary of Contents for 2820A-02
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