Service manual

UX-A255U
4) Signal selection
The following signals are used to control the transmission line of TEL/
FAX signal. For details, refer to the signal selector matrix table.
[Control signals from output port]
5 – 11
5. CI detection circuit
• CI is detected by the photo coupler which is integrated in series in
the primary side TEL circuit well proven in the existing unit.
6. Signal/DTMF transmission level & receiving level
• Signal transmission level setting: ATT -8 dB Circuit output: -11 dBm.
• DTMF transmission level setting: HF -2.5 dBm LF -4.5 dBm
Thus, set the level.
VOLUME SETTING
LINEOUT A RCVOL DTME VOL A VOL B VOL C
(HIGH) (LOW) MUTE
Receiver volume setting Low 1 1
Middle 1 0
High 0 0
DTMF Transmission Fixed 1 1
volume setting (Receiver)
Key buzzer volume setting Fixed 1 1 1
Speaker volume setting Level1 0 1 1
Level2 0 0 1
Level3 1 1 0
Level4 0 1 0
Level5 1 0 0
Ringer volume setting Low 1 1 1
Middle 0 0 1
High 0 0 0
DTMF speaker volume Level1 1 0 1
setting Level2 1 0 1
Level3 1 0 1
Level4 1 0 1
Level5 1 0 1
OGM playback speaker Level1 0 0 1
volume setting Level2 1 1 0
Level3 0 1 0
Level4 1 0 0
Level5 0 0 0
ICM record speaker Level1 0 0 1
volume setting Level2 1 1 0
Level3 0 1 0
Level4 1 0 0
Level5 0 0 0
Signal Name Description
CML Line connecting relay and DP generating relay
(The circuit is located H: Line make
in the TEL/LIU PWB.) L: Line break
SP MUTE Speaker tone mute control signal
(The circuit is located H: Muting (Power down mode)
in the TEL/LIU PWB.) L: Muting cancel (Normal operation)
Handset reception mute control signal
TELMUTE H: Muting
L: Muting cancel
Handset receiver volume control signal
RCVOL
DTMFMUTE
(The circuit is located
in the control PWB.)
Note: The DTMF sending listed above is DTMF signal
sending in the handset OFF-HOOK mode.
Volume High Middle Low DTMF sending
RCVOL LHH H
DTMFMUTE L L H H