Genesys GDR- COM Series, Installation Manual, Page: 35 / 62

GDR-XXXX NAV/COM INSTALLATION MANUAL
CHAPTER 2 – SYSTEM INSTALLATION
64-000109 Page 35 of 62
ARINC
LABE
L
NAME
ARINC
RX#1
ARINC
RX#2
ARINC
TX
NOTES
030 VHF COM FREQ. X X X 25 KHz tuning
034 VOR/ILS FREQ. X X X
035 DME FREQ. X
040 UHF COM FREQ. X X X
047 VHF COM FREQ. X X X 8.33KHz tuning
173 LOC DEVIATION X
174 GS DEVIATION X
222 VOR BEARING X Includes MB
242 VOR STATION ID X 1
st
word Morse code
244 VOR STATION ID X 2
nd
word Morse code
263 ILS STATION ID X 1
st
word Morse code
264 ILS STATION ID X 2
nd
word Morse code
350
LRU
MAINTENANCE
X BIT status of GDR
D. MIC Audio
There are two microphone audio inputs to the GDR. In dual radio mode, the VHF
MIC is used for VHF transmission and the UHF MIC is used for UHF transmission.
In single radio mode, only the UHF mic input is used for both bands.
The MIC input has a 150 Ohm impedance, biased at 12 VDC on MIC+, and has an
input range of 0.25 to 2.50 Vrms for full modulation. A typical input setting of 0.27
Vrms is recommended, which minimizes cabin noise.
Conn Pin Description
P1 7 VHF MIC-
P1 8 VHF MIC+
P1 10 UHF MIC+
P1 11 UHF MIC-
E. COM Audio and SIDETONE
The UHF and VHF bands have separate RX audio outputs and are configurable to
combined Sidetone on these outputs. Both bands have a shared Sidetone output,
when Sidetone level control by the audio panel is desired. The GDR must be
configured to provide Sidetone on the receiver output.
All audio outputs are floating differential, but may be installed single-ended with the
negative output grounded if required. Differential connection to the audio panel is
recommended for noise immunity.
Each COM audio output can generate up to 100 mW into a 600 Ohm load or 7.75
± 0.5 Vrms. Normal production setting is for 100 mW into 150 Ohm load at 3.87 ±
0.5 Vrms. Desired audio levels depend on the audio panel and headset
impedance used in the aircraft. If the audio panel has an emergency mode, the
radio may be required to drive the headset directly and may require a different
audio output level.