Specifications

SECTION III
MODEL 560 INSTRUMENTATION AND AVIONICS
A comparator annunciator displays a flashing ACT to the left of the active frequency display when the
selected control radio frequency is not identical to that of the radio receiver-transmitter unit.
An OFF/ON/SQ OFF function switch is concentric with a volume control. The ON position provides
power to the system and SQ OFF position disables the automatic squelch circuits which compensate for
varying noise levels during normal operation. The squelch threshold is non-adjustable; however, the
squelch circuits can be disabled by selecting SQ OFF. Disabling the squelch may improve reception in
some high noise conditions where the squelch may suppress a very weak signal.
HF COMMUNICATION
HF KHF-950 With KFS 594 CONTROL (Optional)
The KHF-950 with KFS-594 Control is a 150-watt transceiver system that provides 280,000
frequencies at 100 Hz increments with 19 channel preset capability in the HF band (2.0000 to 29.9999
MHz). It operates in AM and single sideband. Upper sideband (USB) is normally used for sideband
operation, but lower sideband (LSB) is available where that mode may be used.
In TEL (A3J) mode, any of the ITU telephone channels (401 through 2241) may be selected.
CONTROLS AND INDICATORS
All controls and indicators are located on the radio set control, which is mounted on the associated
instrument panel (center or right). The smaller left most knob controls power to the receiver/transmitter and
controls the volume of the received audio. Clockwise rotation turns the unit on and increases the volume.
The larger left most knob controls the threshold of the received signal above which the audio is
enabled (squelch). Turning the knob clockwise reduces the signal threshold (decreases the squelch).
The larger right most knob selects the emission modes; LSB, lower sideband; USB, upper sideband;
AM, amplitude modulation; and TEL (A3J, or ITU mode). When LSB, USB, or AM is selected, the radio is
set to the corresponding mode and a frequency is displayed in the control head, which may be directly
selected on one of the 19 user programmable channels. When TEL (A3J) is selected, the radio is set to
the corresponding mode and an ITU channel is displayed in the control head.
The smaller right-most knob, when pushed in, moves the cursor (represented by a flashing digit) from
left to right. One push increments the cursor one digit to enable that digit to be selected as required.
When the small knob is turned, it increments or decrements the digit selected by the cursor.
I 56OMB-01 Configuration AA 3-21