(7) Light sensor. This built-in light sensor
automatically controls display brightness.
(8) Volume control. The volume control is
concentric with the power and mode switch.
(9) Power and mode switch. The power
and mode switch contains three detented positions
placarded OFF, ON, and HLD. The ON and OFF
position switches system power. The hold ( HLD)
position allows the navigation receiver frequency to be
changed while holding the DME in its present frequency.
(10)Annunciators. The receiver control unit
whenever a preset frequency is being displayed in the
lower window. The RMT annunciator is not used in this
(11)Preset frequency display. The preset
(inactive) frequency and diagnostic messages are
displayed in the lower window.
(12)Compare annunciator. An annunciator
frequencies are being changed. The ACT annunciator
flashes if the actual radio frequency which the receiver is
tuned to is not identical to the frequency shown in the
active frequency display.
It is not practical to provide monitoring for all
possible that erroneous operation could
occur without a fault indication. It is the
responsibility of the pilot to detect such an
occurrence by means of cross-checks with
redundant or correlated information available
in the cockpit.
receiver and the CTL-32 NAV control are turned on as
BATTERY switch (overhead control
panel, fig. 2-9) - ON.
switch (overhead control panel, fig.
2-9) - ON or EXT PWR as required.
EFIS power switches (2, overhead
control panel, fig. 2-9) - ON.
Active Frequency Display
Power and Mode Switch
Annunciators (MEM, RMT, HLD)
Preset Frequency Display
Figure 3-24. VHF Navigation Receiver Control Unit