User guide

PM4/8/12/16 & PM4/8-SA Installation and User Guide v1.0
42
Terminating the Digital Paging Interface
The Cloud Digital Paging Interface must be correctly terminated at its ends for error-
free operation. In systems using a single PM connected to a host mixer via the digital
interface (such as the Cloud DCM-1), the terminations should be ON at both the PM
and the mixer. In systems with multiple PMs, only the mixer and the PM at the ‘end’ of
the chain should have their terminations set ON; ‘intermediate’ PMs should have their
terminations set to OFF.
CDPM
GAIN (dB)
IN
THRU
-10
+10
INOUT
OUT
Mixer
Mixer
OUT
OUT
Termination ON
Termination ON
Termination OFF
CDPM
IN
THRU
CDPM
IN
THRU
DCM-1 #2
DCM-1 #1
Termination ON
Termination
ON
Termination ON
Termination OFF
Termination
ON
CDPM
GAIN (dB)
IN
THRU
-10
+10
The termination is set in the PM with jumper J4. See “PCB layout diagrams” on page
49 for jumper locations. The factory default setting is for the termination to be set
ON. If the PM being con gured is ‘mid-chain’, with both its CAN PORT IN and CAN
PORT OUT connectors in use, set the termination to OFF by removing the jumper.