Clear-Com Intercom Systems
MR-202/MR-204 Two- and Four-Channel Headset Stations
© Clear-Com Intercom Systems 2000
11
Rev. B
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Excessive crosstalk
Scenario 1
High DC resistance in ground return.
Solution: Use heavier cable; add additional conductor(s) to ground return. If
the cable run is exceptionally long, consider adding and using the EB-4W 4-
Wire Option Module.
Scenario 2
Multi-channel cable pairs are not individually shielded.
Solution: Replace cable with individually shielded pairs.
Scenario 3
Headset cables are not wired properly or shielded properly.
Solution: Correct wiring. Use headsets with properly shielded wiring.
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The Call signal does not function.
Scenario 1
Excessive DC loading of intercom line.
Solution: Remove any audio transformers or other equipment which may be
connected across the intercom line. If equipment other than Clear-Com
intercom equipment must be connected to the intercom line, please contact
Clear-Com application or service personnel for advice.
Scenario 2
Far too many terminations on the intercom line.
Solution: Check all main stations and power supplies to make sure each
intercom channel is terminated at only one point.
Scenario 3
Plug P1 missing on circuit board.
Solution: Plug P1 must be installed in the J1 jack if the EB-4W or EB-TW
options are not used.
