Service manual

[Signals for status recognition according to input signals]
Signal Name Function
RHS
H: The handset is in the on-hook state.
L: The handset is in the off-hook state.
CI Incoming call (CI) detection signal
HS
H: The handset or external telephone is in
the on-hook state.
L: The handset or external telephone is in the
off-hook state.
P.E
L: No recording paper.
H: Recording paper exists.
DRSNS
H: Door open.
L: Door close.
[Other signals]
Signal Name Function
TEL IN Receiving signal from line or modem
TEL OUT Transfer signal to line
TXOUT
Transmission (DTMF) analog signal output
from modem
RXIN
Reception (DTMF, others) analog signal
input into modem
(Example: Fax signal send)
NO Signal Name (CNLIU) NO Signal Name (CNLIU)
1 +24VA 8 RHS
2 DG 9 TXOUT
3 PE 10 RXIN
4 +5V 11 TELMUTE
5 CML 12 DRSNS
6 CI 13 TELOUT
7 HS 14 TELIN
8. Sensor circuit
For the recording paper sensor (P.E), when there is recording
paper, the photo transistor in the light receiving side is ON and the
detection level is LOW. When there is no recording paper, the
photo transistor in the light receiving side is OFF and the detection
level is HIGH.
9. Cl detection circuit
The CI detection circuit detects the CI signals of 15.3 Hz to 68 Hz.
A CI signal, which is provided to the photo-coupler PC1 through
the C1 (0.82 uF), R3 (22 K), and ZD3 when the ring signal is
inputted from the telephone line.
10. Power supply and bias circuits
The voltages of +5V and +24VA are supplied from the control
PWB unit.
Fig. 7
H
L
HS DETECTOR
CML
CI DETECTOR
0
1
SPEAKER
TEL
LINE
+5V
+24VA
DG
TEL MUTE
CI
TEL MUTE
SP MUTEI
CI
BZCONT
RCVOL
TXCONT
BZCONT
VOL C
VOL B
VOL A
TELOUT
TEL IN
EXT.
HANDSET
RXIN
TXOUT
CML
HS
GAIN-C
TXCONT
SIGTX
SIGRX
0
1
RCVOL
0
1
GAIN-C
CML
HS
XFCR-MVP
MODEM
(R96DFXL-CID)
CONTROL PWBTEL/LIU PWB
UX-510U/UX-510C/UX-500U
UX-500C/FO-1460U
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