通航信息_通航_通用航空_General Aviation

3. DESCRIPTION
A. A78 COMM./VOR-ILS/GPS transceiver (Figure 3)
The A78 COMM./VOR-ILS/GPS transceiver enables air-to-ground or air-to-air communications within the 118.00 MHz to 136.975 MHz frequency range.
The COMM.NOR-ILS/GPS transceiver is a rectangular box installed in an attachment rack. Connections are made through four electrical connectors and four antenna connectors located on the box rear face.
For communication function, the equipment panel front face includes :
- A digital display (1) subdivided in three main windows. The COMM. function display window (3) is located in the top left part of the display. This window displays the frequency being used (active frequency) and the window below displays the standby frequency,
- ".C" button (4) enables equipment energization, audio level control and squelch control, "C<->" pushbutton (5) is used to transfer the standby frequency in active frequency and vice versa,
- two concentric knobs (2) are used to modify standby frequency when the cursor function is enabled. If necessary, push momentarily the inner concentric knob in to activate cursor function.
Without "Ground Clearance"
A78 COMM.NOR-ILS/GPS transceiver is electrically supplied by "BUS 1" bar via a radio master relay. It is protected by CB 86 "COM 1" circuit breaker.
With "Ground Clearance"
In normal operation, A78 COMM./VOR-ILS/GPS transceiver is electrically supplied by "BUS 1" bar via a radio master relay and via K201 relay contacts in rest position. It is protected by CB 86 "COM 1" circuit breaker.
When "Ground Clearance" function is actuated, A78 COMM./VOR-ILS/GPS is electrically supplied by the battery via K201 relay contact in ON position. The installation is then protected by CB 16 circuit breaker. The circuit breaker is attached to frame No. 4 near starter relay.
All
A78 COMM./VOR-ILS/GPS transceiver is mounted on PL30 radio rack.
B. E31 Antenna
The E31 antenna is a vertical polarization aerial, with a 50-ohm impedance intended for omni-directional transmission and reception of signals within 118 to 136.975 MHz frequency band.
The E31 antenna ensures the propagation and the reception of data-conveying electromagnetic waves. The E31 antenna is mounted on top of the fuselage at the rear of C6 frame.
AIAI
Validity : GNS 530 23-12-00 (c., Page 2 JUN 04
 
A - A78 COMM.NOR-ILS/GPS transceiver
 
Variante de localisation Alternate location
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COM 1 installation — Identification and location of components
Figure 1
AIAI
Validity : GNS 530 23 12 00 (CQ) Page 3 JUN 04
　
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