used to set the 10 kHz digits when pushed in. When
pulled out it is used to set the 1 kHz digits. When the
display is changed to 2182 kHz the smaller knob will
change the ones digits (from 2180 to 2189 kHz)
whether pushed in or pulled out.
When in the active entry mode, the tuning knobs
operate the same as they do in the standby entry
mode, but will change the active digital display
frequency rather than the standby frequency.
(c) Channel Mode. When the unit is in
the channel mode, turning either tuning knob will
change the channel number in the upper display and
the corresponding frequency in the lower display.
(d) Program Mode. When the unit is in
the program mode, the tuning knobs are used to select
the channel number in the upper display (when
flashing), or the channel frequency in the lower display
(4) Mode Switch. A momentary push-button
switch, placarded MODE, is used to select the
operating mode of the ADF receiver. Each press of
the MODE switch cycles the system through the ANT,
ADF, ANT/BFO, and ADF/BFO modes. The current
mode is shown on the display.
(5) Channel Switch. A momentary push
button switch, placarded CHAN, located on the lower
portion of the ADF control unit, is used to put the unit
into the channel and program modes. Momentarily
pressing the CHAN switch while in a frequency mode
puts the unit into the channel mode. Holding the
channel switch pressed for longer than 2 seconds puts
the unit into the program mode.
(6) OFF / VOL / PUSH Control. A control
knob on the front of the ADF control unit placarded
OFF / VOL / PUSH controls the operation of the unit.
Turning the knob in the clockwise direction from the
OFF position (detent) applies power to the unit, and
audio volume output is increased as the knob is turned
further to the right. Pressing PUSH overrides the
automatic squelch circuitry. Turning the knob
clockwise past the automatic squelch threshold, while
the automatic squelch circuitry is overridden, will allow
headphones or speaker and demonstrate whether the
receiver is working or not, and allow setting of audio
volume. To return the transceiver to automatic
squelch control, press the PUSH control knob again.
c. Frequency/Channel Selection Modes. The
ADF receiver control unit may be operated in the
frequency mode (either standby entry or active entry),
channel mode, or program mode.
(1) Frequency Modes. The ADF receiver
control unit may be operated in standby entry or active
(a) Standby Entry. When the unit is
operated in the standby entry frequency mode, a new
frequency is set on the standby digital display, using
the tuning knobs. When the operator is ready, the
frequency is then transferred to the active display by
pressing the frequency transfer switch.
(b) Active Entry. When the unit is
operated in the active entry frequency mode, a new
frequency is set on the active digital display using the
tuning knobs. The active entry mode is entered from
the standby entry mode by pressing the transfer switch
for longer than 2 seconds. The standby digital display
will be blank while the unit is in the active mode.
(2) Channel Mode. When the ADF receiver
control unit is in the channel mode, the upper digital
display will show a channel number (1 through 9), and
the lower digital display will show the frequency
assigned to the channel number in the upper digital
display. The tuning knobs will change the channel
number and corresponding frequency shown on the
momentarily pressing the CHAN button located on the
ADF receiver control unit. If there are no valid
frequencies programmed, the unit will display a CH 1
in the upper display and dashes in the lower display.
The unit can be changed from the channel mode to the
frequency mode in three ways.
(a) Momentarily pressing the transfer
switch will return the unit to the frequency mode,
placing the channel frequency in the active display and
the previous active frequency in the standby display.
(b) Momentarily pressing the
switch will return the unit to the frequency mode, and
will return the active and standby displays to what they
displayed prior to entering the channel mode.
(c) The unit will return to the frequency
mode if no knob activity takes place for 5 seconds
after the unit was put into channel mode. When
returned in this manner, the channel frequency will be
put into the standby display with the active frequency
remaining as it was before entering channel mode. If
no frequencies were programmed, the frequencies will
remain the same as they were before entering channel