TELEREADER CWR-685E, Service Manual

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NOR/REV
In REV position, J1-2 terminal on MODEM PCB is connected to GND.
BAUD 6-position switch
One of the terminals J2-2 to J2-7 on MODEM PCB is connected to GND.
SHIFT 3-position switch
When 425 is turned on, the J1-12 terminal on MODEM PCB is connected to GND.
When 850 is turned on, the J1-11 terminal on MODEM PCB is connected to GND.
TONE LOW
When turned on, the J1-10 terminal on MODEM PCB is connected to GND.
RX/TAPE
In RX position, the AF IN RX terminal and AF OUT terminal in rear panel and J9-1 terminal
on main PCB are connected together.
In TAPE position, the AF IN TAPE terminal and AF OUT terminal in rear panel and J9-1 ter-
minal on main PCB are connected together, and the J7-16 terminal on main PCB is connec-
ted to GND.
SEND/AUTO/RECEIVE
In SEND position, the SW OUT PHONE terminal in rear panel is connected to GND, and the
J8-5 terminal on main PCB is connected also to GND.
In RECEIVE position, the J8-8 terminal on main PCB is connected to GND.
3.2 Actions of external control signal output ports
This paragraph describes the performance of output ports on the main PCB in which outputs vary
depending on the setting of each switch or commands. These outputs are controlled by the com-
puter.
J10-5
When RX/TAPE selector is set to RX side, the level becomes H. When the RESET button is
being pushed down, the level is L.
That is, when the RESET button is pressed, the level is L, and when the button is released,
the level temporarily becomes H, but soon returns to L.
This output controls the J1-1 terminal on MODEM PCB.
Output port
The IC27 is an 8-bit latch IC. The external control signals of this system are mainly deliver-
ed from this IC. While the RESET button is kept depressed, this output remains at L level.
Pin 15
An output is delivered to J10-4 terminal. The output becomes H level when sending RTTY.
This output controls the J6-1 terminal on MODEM PCB, and opens the AFSK output gate of
RTTY when the level is H to delivery an AFSK oscillation signal.
Pin 16
A transmission/reception changeover signal for software control is delivered. When the le-
vel is H, the SW OUT REMOTE is turned on, and the reading gate of CW audio demodula-
ted signal is also closed.