Specifications

October, ‘03 Comdial 75
DX-80 Installation & Maintenance
No sound heard
over loudspeaker in
speakerphone
mode.
Another digital
telephone
Connection /
component
failure
Press the ON/OFF button and listen for dial
tone over the loudspeaker.
Call a known good extension. (The called
extension should use the handset for this test.)
Verify two-way connection. If you cannot hear
the called extension, verify that MUTE is not
enabled at the called extension (Status Lamp
flashing red).
Lift the handset and verify two-way connection
using handset. If verified as a speakerphone
problem, replace the telephone.
Static and / or noise
can be heard during
a conversation.
Process of
elimination.
Industry
standard
technician
testing tools
(lineman's test
set, etc.)
Another
extension
While on intercom call is the static heard only
when connected to one particular extension?
Examine that extension.
Station
cabling/MDF
wiring
If static exists on all calls, check station
cabling/wiring and all MDF connections,
correct any problems.
Extension
apparatus
If noise persists, change-out swappable
components (handset, handset cord). If noise
continues try a known good extension
connected to this station cable.
Telco problem If static/noise is heard on CO lines only,
determine if other extensions also hear the
noise/static.
If so, are several CO lines affected or only a
few.
Disconnect CO line at interface point and
connect Lineman's test set to the same point of
connection ahead of the system. If noise/static
persists, contact the local servicing telephone
company and request repair.
If noise/static can be isolated to the DX-80
equipment, verify which CO line ports are
affected (which CO ports seem to have noise/
static), replace interface modules as required.
Symptom(s)
(Continued)
Diagnostic
Aid
Cause(s) Action