b. VOL control - As required.
9. Shutdown procedure:
3-24. ADF RECEIVER (ADF-60).
a. Introduction. The ADF receiver (FIG. 3-16)
provides aural reception of signals from a selected
ground station and indicates relative bearing to that
station. The ground station must be within the
frequency range of 190.0 to 1749.5 kHz. The ADF
receiver has three functional modes of operation. In the
antenna (ANT) mode the ADF receiver functions as an
aural receiver, providing only an aural output of the
received signal. In automatic direction finder (ADF)
mode, it functions as an automatic direction finder
receiver in which relative bearing to the station is
presented on an associated bearing indicator, and an
aural output of the received signal is provided. The
tone (TONE) mode provides a 1000-Hz aural output
tone when a signal is being received to identify keyed
continuous wave (CW) signals. The ADF receiver is
powered through the 2-ampere ADF circuit breaker
located on the overhead circuit breaker panel.
b. ADF Control Unit Operating Controls,
Indicators, and Functions. All operating controls for the
ADF receiver are located on the ADF control unit.
(1) Frequency Display. Indicates the frequency
to which the ADF receiver is tuned.
(2) TEST Button. Activates diagnostic self-test
(3) TONE/OFF Switch. Permits operation of
output tone when signal is received.
(4) Tuning Control. Selects operating frequency.
(5) OFF/ANT/ADF Switch. The OFF position
removes power from the system. ANT
permits operation as an audio receiver only.
ADF permits automatic direction finding or
c. Normal Operation.
1. Power and mode switch - ANT or ADF.
2. Tuning knobs - Set desired frequency.
a. ANT function Position the power and
mode switch to ANT. The RMI
pointer will park horizontally. Select
ADF on the audio system and adjust
b. ADF function Position the power and
mode switch to ADF. The RMI
pointer will indicate relative bearing
to the tuned station.
receiving a reliable signal, the RMI
pointer will remain parked in the
momentarily park during station
crossings due to signal loss. c.
TONE function Position the TONE/
OFF switch to TONE. A 1000-Hz
tone will identify keyed CW stations.
a. Power and mode switch - ADF.
b. Tuning knobs Tune a nearby NDB,
outer marker, or broadcast station.
c. TEST switch Depress. RMI pointer
will rotate 90 degrees from the
previous valid indication. Release
the TEST switch and verify that the
RMI pointer returns to that indication.
If the signal received is weak or of poor quality, the
bearing pointer rotation will be slow.
3-25. TACAN SYSTEM (AN/ARN-154).
a. Description. The TACAN (FIG. 3-17) system
operates in conjunction with TACAN and VORTAC
ground stations to provide distance, groundspeed, time
to station, and bearing to station. It operates in the L
band 1000 MHz frequency range on one of 252
preselected frequencies, 126 X mode and 126 Y mode
channels. Course deviation and distance to TACAN or
VORTAC stations are displayed on the HSI. Distance,
time to station, and groundspeed are displayed on the
TACAN digital display. The groundspeed and time to
station, are accurate only if the aircraft is flying directly
toward the ground station at a sufficient distance that
the slant range and ground range are nearly equal. The
system is protected a 2-ampere circuit breaker in the
AVIONICS portion of the overhead circuit breaker panel