TM 1-1510-223-10
Figure 3-25. ADF Control Unit
For future developments, the control unit has a
normal frequency range of 190.00 to 1799.5 kHz.
However, when used with the ADF-60, the upper
frequency is limited to 1749.5 kHz. Rotation of either
frequency select knob increases or decreases the
frequency in the preset frequency display. The larger
outer knob changes the frequency in 1000-kHz and 100-
kHz increments (first and second numbers from the left).
The smaller inner knob changes the frequency in 10's,
units, and tenths kHz increments (third, fourth, and fifth
numbers from the left). After the desired frequency is set
in the preset frequency display, it can be transferred to
the active frequency display by momentarily setting the
XFR/MEM switch to XFR. At the same time that the
preset frequency is transferred to the active display, the
previously active frequency is transferred to the preset
display. The ACT annunciator on the control flashes
while the receiver is tuning to the new frequency.
NOTE
If the ACT annunciator continues flashing, it
indicates that the receiver is not tuned to the
frequency displayed in the active display.
The ADF control unit has a memory that permits
storing up to four preset frequencies. Once stored, these
frequencies can be recalled to the preset display by
positioning the XFR/MEM switch to the MEM position.
The storage location (CH 1 through CH 4) for the recalled
frequency is displayed in the active frequency display
while the XFR/MEM switch is held in the MEM position.
All four stored frequencies can be displayed one at a time
in the preset display by repeatedly positioning the
XFR/MEM switch to the MEM position. After the desired
stored frequency has been recalled to the preset display,
it can be transferred to the active display by momentarily
positioning the XFR/MEM switch to the XFR position.
During normal operation, all frequency selections and
revisions are done in the preset frequency display.
However, the active frequency can be selected directly as
described in the following paragraph.
(3) Direct active frequency selection. The active
frequency can be selected directly with the frequency
select knobs by pushing the ACT switch for 2 seconds.
The active frequency selection mode is indicated by
dashes appearing in the preset display. The ACT
annunciator will flash as the frequency select knobs are
turned to indicate that the transceiver is being retuned.
NOTE
If the ACT annunciator continues flashing, it
indicates that the receiver is not tuned to the
frequency displayed in the active display.
3-62
