R46 Circuit Diagram (6/15) - Oki OKIFAX4550 Maintenance Manual

4.4

R46 Circuit Diagram (6/15)

1. Block diagram
R46-PCB circuit diagram (6/15) shown the consists of Modem (33.6 kbps).
Modem consists the following functions:
• Modulation/demodulation
Modulation type:
1) ITU-T Rec. V34 (33600/31200/28800/26400/24000/21600/19200/16800/14400/12000/
9600/7200/4800/2400 bps) for G3 picture data.
2) ITU-T Rec. V17 (14400/12000/9600/7200 bps) for G3 picture data.
3) ITU-T Rec. V29 (9600/7200 bps) for G3 picture data.
4) ITU-T Rec. V27 ter (4800/2400 bps) for G3 picture data.
5) ITU-T Rec. V21 channel 2 (300 bps) for binary signals defined in ITU-T Rec. T.30.
• Automatic adaptive equalizer for G3 receive data with 300 bps data excluded.
• Generation of signal tones
• PB tone (multi-frequency tone) generation
• Detection of single tones
• D/A converter for send data (TX)
• A/D converter for receive data (RX)
• Amplitude equalizer for RX
• Selectable attenuation for TX
• Automatic gain control
Figure A.22 shows the related signals of Modem.
CPU1
NMDRST
SH7034
28.224 MHz
X3
X'tal
41309401TH Rev.4
IC6
D0 to D7
A1 to A5
V34INT
V34CS
NRD3
NWR3
IC10
IC10
Modem
33.6 kbps
Figure A.22 Related Signals of Modem
R46
IC2
IOGA6
CN10 CN3
7
S
R
RP
NCU
A4 S
A2
R
334 /