PictureTel Concorde 4500 Servicing Manual page 110

TROUBLESHOOTING
If you have these
symptoms...
Echoing from the
microphones
4-12
Table 4-4: No Audio Checklist (Continued)
1. Make sure that the microphones are not placed directly in
front of or next to the speaker at both sites.
2. Try to isolate the problem to a single site. Perform a local
Channel Loopback test at both sites. If echo is heard at one
site then that site is the source of the problem.
3. Make sure that IDEC is enabled at each site. Check the IDEC
setting in the Audio Configuration menus.
4. Try moving the PowerMics further away from the speaker,
and then perform a Local Channel Loopback test. During the
test, talk continuously in a normal voice and walk slowly
around the PowerMics until a full circle has ben completed.
This procedure will train the PowerMic and IDEC
systems. After completing the procedure check for echo. If
it still exists, then there may be a faulty PowerMic or
Audio Interface board.
Do this...