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MINI-MODEM (56 KBPS DATA/FAX MODEM)
Figure 3-4. Mini-Modem Front Panel.
• TD: Transmit Data. The TD LED flashes when
data is being transmitted (on for a space, off for a
mark). Signals on this circuit are generated by the
terminal and transferred to the transmitter of the
Mini-Modem. The transmitting terminal should
hold this line in the marking state when no data
is being transmitted, including intervals between
characters or words. The TRANSMIT (TD) LED
indicates the status of this circuit.
• RD: Receive Data. The RD LED flashes when data
is being received (on for a space, off for a mark).
Data signals received from the remote Mini-
Modem are presented on this line. The RECEIVE
(RD) LED indicates the status of this signal.