Board Descriptions
A - 55
OF 5300/5600 Serv Man, P/N 59278301
A3.7
UNC5 (NCU) Circuit Diagram
Note: The relationship between NCU and optional boards (NTIF, TEL, HOOK, etc.) are shown
in A3.11 facsimile transceiver (page A3-101).
1.
Block diagram
•
Figure A3.7.1 shows a block diagram of UNC5 (NCU) circuit.
2.
General functions of this circuit are as follows:
1)
Generates and detects signals to be exchanged with a telephone exchange or
network in Phases A and E defined by ITU T.30.
•
Loop formation for call origination
•
Line current detection (see note 1) before call origination
•
Dial tone detection (see note 1)
•
Generation of dial pulses (see note 2)
•
Busy tone detection (see note 1)
•
Ringing signal detection
2)
Sends various data and signals from the R44/M17 board to the telephone line after
amplification.
•
Picture data/Protocol/Tonal signals/PB tone, etc.
3)
Sends the following signals received from the line to the R44/M17 board as data
after amplification.
•
Picture data/Protocol/Tonal signals, etc.
Note 1: This procedure may be omitted depending on the dial parameters.
Note 2: MF (Multi-frequency) tone is generated by the modem and transferred to
the telephone line via the NCU board.
Summary of Contents for OF5600
Page 376: ...Illustrated Parts List D 2 OKIFAX 5300 5600 Service Manual P N 59278301 1 Cabinet Assembly...
Page 388: ...Illustrated Parts List D 14 OKIFAX 5300 5600 Service Manual P N 59278301 5 Scan Unit...
Page 394: ...Illustrated Parts List D 20 OKIFAX 5300 5600 Service Manual P N 59278301 8 Option Telephone...
