Garmin APOLLO GX SERIES, Service Manual

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Garmin AT Rev --
7-16 GX Service Manual © 2004 Garmin AT
Performance Specifications
Transmitter Performance Specifications
Parameter Specification
Class D
Output Power 8 W minimum carrier at > 12 VDC in 6 W minimum carrier at 10 VDC
in. Transmit is locked out below 9 VDC input (no modulation).
Frequency range 118.000 MHz to 136.975 MHz, 760 channels
Frequency tolerance
±15 PPM from -20
°
C to +70
°
C
Microphone input Two inputs: standard carbon or dynamic MIC with integrated pre-amp
providing minimum of 70 mV RMS into 1000
Ω load.
Modulation capability 1. 85% with 1000 Hz at 100 mV to 1000 mV RMS microphone input
Audio frequency distortion <10% at 85% modulation at 350 Hz to 2500 Hz
Audio frequency response <4 dB variation with 350 Hz to 2500 Hz, 85% modulation
Carrier noise >35 dB down
Sidetone output Up to 280 mW into 100 Ω load, 120 mW into 500 Ω load
Duty cycle 100%
Stuck mic time-out 35 seconds, reverts to receive
Transmit key Input pull low to enable transmitter
Receiver Performance Specifications
Parameter Specification
Frequency range 118.000 MHz to 136.975 MHz, 760 channels
Sensitivity 1 µV (2 µV hard) for 6 dB SINAD with 30% modulation at 1000 Hz
Selectivity <6 dB variation at ±7 kHz, > 60 dB at ± 22 kHz
Speaker audio output level 12 watts into 4 Ω , 8 watts into 8 Ω
Headphone audio output
level 2. 280 mW into 100 Ω ,120 mW into 500 Ω
Distortion <5% at rated output at 1000 Hz
AGC characteristics < dB variation in audio output from 5 µV to 100 mV input 15% to 90%
modulation
Squelch control Automatic squelch with manual override