is connected to the input of the facsimile
Converter CV-2C/TX and Exciter Unit
transceiver.
O-5B/FR (earlier models must be modi-
(2) Subcarrier frequency modulation (SCFM).
fied) frequency-shift signals can be trans-
When the facsimile transceiver is con-
mitted over a conventional continuous-
nected to such auxiliary equipment as
wave (cw) radio transmitter. When
transmitting, the am output of Facsimile
Converter CV-2(*)/TX, the converter
Transceiver TT-1(*)/TXC-1 is fed into
output is fed into a conventional am
radiotelephone transmitter and the radio
the converter. A varying direct-current
signals are described as narrow band
(dc) output is taken from the converter
subcarrier frequency modulation. The
and fed into frequency-shift Exciter
radio signals consist of a radio-frequency
U n i t O-5B/FR. The output of the
(rf) carrier modulated by a constant-
exciter unit excites the cw transmitter
amplitude audio signal, the frequency of
and a frequency-shift radio signal is
transmitted. When receiving, a stable
which is varied to carry facsimile intelli-
am communication receiver with a
gence. When this system is used for
crystal-controlled, high-frequency (hf)
receiving, a conventional am radio
receiver, the same converter, and the
oscillator and the converter are used to
convert the frequency-shift signals to am
same facsimile transceiver are used.
signals. When using receivers that do
The converter changes the subcarrier
not use crystal-controlled conversion, the
fm signals back to am signals, which are
required for operation of the transceiver.
stable output of additional auxiliary
equipment Frequency Meter BC-221 is
(3) Frequency-shijt modulation. When Fac-
simile Transceiver TT-1(*)/TXC-1 is
required and is used with Converter CV-
used with two auxiliary equipments,
2C/TX to receive frequency-shift signals.
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