concentric knob to select the channel and repeat the
To return to an operating mode,
push the PGM button.
The mode for each channel (LSB, USB
or AM) is stored along with the
frequency. If the mode is changed, the
system will receive and transmit in the
mode selected for transmit.
Shutdown. OFF/VOLUME switch OFF.
HF Command Set Emergency operation.
3-12. SINCGARS AN/ARC-201(V).
Description. The Sincgars AN/ARC-201(V)
radio system (fig. 3-5) provides VHF-FM radio
communications, in single channel and ECCM mode of
operation. The frequency range is 30 to 87. 975 MHz
channelized in tuning increments of 25 kHz. In addition
a frequency offset tuning capability of -10 kHz, -5 kHz,
5 kHz and
10 kHz is provided in both receive and
transmit modes; this capability is not used in the ECCM
mode. The system provides improved immunity from
the threat of electronic warfare, and provides for secure
communication of voice and data signals through
interfacing with the KY-58. The system is protected by a
10-ampeire circuit breaker, placarded FM, located on
the overhead circuit breaker panel.
The Sincgars FM radio set is a combination
control/transceiver, installed in the pedestal extension
for convenient operation by the pilot or copilot. The
front panel control allows the pilot or copilot to instantly
switch to any one of 20 preset channels.
Controls and functions.
The IFM RF PWR switch is not used
on this installation
Function Switch. The function switch
is used to select the basic operational condition within
the radio transceiver (RT). It is a nine-position switch
with positions one, eight, and nine being isolated switch
positions. Isolated switch positions require a pull and
turn operation to actuate. Position one is OFF, eight is
Z-A (zero all) and position nine is STOW (storage).
Actions initiated by these switch settings are sensitive to
the operation of the RT and are therefore designed to
require a conscious effort of the operator to actuate.
Operative positions of the function switch are as follows:
OFF. All primary power is
removed from the RT. The memory holding battery,
however, is connected to its associated circuitry,
providing the retention of stored frequency hop (FH)
parameters, time and preset frequencies.
TEST. When selected, the
major components of the subsystem are examined to
verify their operation. The RT and the ECCM module
are both tested under micro-processor control. The
results of the self-tests, as well as the presence of the
ECCM module, are presented on the front panel
SQ ON (Squelch On). Primary
power is applied and operation will be by normal, locally
controlled actions. The squelch is enabled and the RT
operation modified by other front panel controls. The
radio's receiver audio output is connected to the No. 2
communications receiver switch of the audio control
panel. Keying of' the transmitter is accomplished by
pressing the Control Wheel switch, placarded INPH
XMT MIC, to the second (XMT) level.
Operation of the RT with the switch in this position is
identical to the ON position except the squelch circuits
are disabled. This position provides the capability to
communicate at extremely low input levels if required.
LD (Load). In this switch
position, all primary power is applied to the RT and the
transmitter is enabled. With the function switch in LD,
loading of preset frequencies is accomplished by normal
keyboard entry in conjunction with the PRESET switch.
Also, time may be set with the switch in LD. ECCM net
parameters and lockout channels are also filled with the
switch in this position, providing an ECCM module is in
the RT, by connecting the appropriate fill device to the
FILL connector and pressing the keyboard H LD button
LD-V (Load Variable). When
selected the TRANSEC variable is loaded into the RT
providing an ECCM module is in the RT. The fill
device is connected as in LD and the keyboard H LD
button pressed once to initiate the transfer.
Z-A (Zero All). This switch