Technical information

Technician’s Handbook
82
Test/Verify (E&M)
Loop back to self whenever more than 1 E&M type V circuit is available.
Verify far-end circuits by activating near-end M lead and listening for far-
end dial tone.
Verify near-end circuits by activating near-end E lead and listening for
near-end dial tone.
Verify that appropriate voltages are present on E&M leads in each call
state.
Digits
M toggles (Rotary) or
DTMF through audio path
E toggles (Rotary) or
DTMF through audio
path
Stop Dial
E lead goes active; goes
inactive when ready to go
-
Receipt of Digits
Audible Tones - Busy,
Reorder, Ringback depen-
dent upon digits dialed and
called party condition
Audible Tones - Busy,
Reorder, Ringback gen-
erated and sent to call-
ing party dependent
upon digits received
and called party condi-
tion
Answer
Supervision
E lead goes active M lead goes active
Disconnect
Supervision
Near-end termination:
M lead goes inactive;
E follows
Far-end termination:
E lead goes inactive;
M follows
Near-end termination:
M lead goes inactive;
E follows
Far-end termination:
E lead goes inactive;
M follows
Table 9: E&M Trunk Summary (continued)
Signal
E&M Trunk PBX
Outgoing
E&M Trunk PBX
Incoming
(Sheet 2 of 2)