Tone Send Test - Oki OF5900 Maintenance Manual

7.12

Tone Send Test

Start
Perform TONE SEND TEST.
(See 6.8.)
Connect leads of frequency
counter (or oscilloscope)
across the line terminals
L1 and L2.
Tones appear at
L1 and L2?
Yes
End
OKIFAX 5700/5900
No
Tones appear across Pin 2 (S)
and Pin 1 (0V) of CN201 (C34 or H34)?
Yes
Tones appear across Pin A8, B8 (S)
and Pin A12, B12 (0V) of CN12 (R76)?
Yes
Replace WN5 Board.
Solved?
No
Replace MCNT (R76) Board.
Note 1 : The tonal frequency (2100 Hz) will be sequentially
sent for 5 seconds on the line terminals L1 and L2.
Note 2 : As an example, signal route uses the WN5 (NCU)
board.
No
Replace C34 or H34
Modem board.
Signal route:
IC202-9 IC203-6, 7
IC203-2, 1
No
Replace MCNT (R76) board.
Signal route:
CN11-A25
Signal route:
CN3-15, 16
CN1-3, 4
Yes
Possible cause:
CML signal
7 - 15
CN201-2
CN12-A8, B8 (S)
T1-3, 1
Return to section 7.1