TM 11-7025-234-23
Table 1-3.
Interface Signal Descriptions -- Continued
CCITT
EIA
Description
RS-232C
Signal Name
V.24
J1
--
--
A positive pulse will cause an
18 Remote Audio Loopback
audio loopback at a remote modem.
110
A positive level from the modem in
21 Signal Quality Detector
CG
response to a jumper-selectable
EQM Bad or ERR Bad signal.
23 Data Signal Rate
To supply a data rate indication to
CH/CI
111/
the terminal, position the CH/CI
112
Selector
jumper, located on the A3 board,
to the CI position. J1-23 will be
negative to indicate that 4800 bps
or 7200 bps operating speed has
been selected manually at the
modem. A positive level will
indicate that 9600 bps has been
selected. For external data rate
control, position the CH/CI
jumpers on the A3 board to the CH
position. The external source
will control the rate of the
modem. A negative level will
switch the modem to the lower
operating speed, and a positive dc
input will select the higher
operating speed.
A serial data rate clock input from
24 Transmitter Signal
DA
113
the data source. Positive clock
Element Timing
transitions correspond to data
transitions.
A transmit data clock output for
15 Transmitter Signal
DB
114
Element Timing
use by an external data source.
Positive clock transitions
correspond to data transitions.
A receiver data rate clock output
17 Receiver Signal
DD
115
for use by the external data
Element Timing
sink. Positive clock transitions
correspond to data transitions.
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