SDX - TWO WIRE LINE CARD


FAX PROBLEMS ON TWC CARDS

CHECK PCS LEVELS ON TWC CARDS.

SDX TWLC (39UPB20000IBMW) AND TWLC WITH VOICE MAIL (39UPB200001AXQ)

1. MF/LD OPERATION

THE TWO WIRE LINE CARD AS SUPPLIED SUPPORTS ONLY MF4 SIGNALLING. TO CONVERT THE CARD INTO LD OPERATION THE DTMF RECEIVER CHIP HAS TO BE REMOVED. THIS CAN BE DONE ON AN INDIVIDUAL CHANNEL BASIS. THE DTMF RECEIVER IS SUPPLIED WITH AN IC SOCKET THEREFORE TO CONVERT CHANNEL A TO LD, REMOVE IC5. TO CONVERT CHANNEL B TO LD, REMOVE IC45.

WARNlNG: ONLY TELEPHONES AND APPARATUS WHICH ARE APPROVED FOR DIRECT CONNECTION TO THE PSTN AND COMPLY WITH B56317 CLAUSE 3 CAN BE CONNECTED TO THESE PORTS. TOTAL REN VALUE OF EACH PORT IS 2.


2. LINE LENGTH MEASUREMENT

BEFORE CARD IS USED THE LINE RESISTANCE MUST BE ACCERTIANED AND THE APPROPRIATE OPM FITTED.

PROCEED AS FOLLOWS:
a. INSTALL THE TWC AFTER REMOVING ANY DTMF RECEIVER CHIPS.
b. ENSURE THE OPM'S ARE REMOVED FROM BOTH PORTS.
c. SHORT THE A AND B WIRES TOGETHER AT THE LJU END.
d. MEASURE AND NOTE THE RESISTANCE BETWEEN PINS 1 AND 4 0F THE RELEVANT OPM SOCKET.
e. REMOVE THE SHORT CIRCUIT AT JACK SOCKET AND INSTALL TELEPHONE INSTRUMENT.
f. FIT CORRECT OPM AS INSTRUCTED BELOW.
g. REPEAT ABOVE ACTION FOR CHANNEL B IF NEEDED.
LINE RESISTANCE OPM CODE
0 to 100 ohms 39YPB10001ATW
100 to 200 ohms 39YPB10001ATX
200 to 300 ohms 39YPB10001AT

 

 
 
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Last revised: November 12, 2021

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