Garmin GPS 400W, Installation Manual

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GNS 400W Series Installation Manual Page 1-5
190-00356-08 Rev. G
1.4.4 COM Transceiver Specifications (GNC 420W and GNS 430W Only) **
Audio Output 100 mW minimum into a 500 load.
Audio Response Less than 6 dB of variation between 350 and 2500 Hz.
Audio Distortion
The distortion in the receiver audio output shall not exceed
15% at all levels up to 100 mW.
AGC Characteristics
The audio output will not vary by more than 6 dB when the
level of the RF input signal, modulated 30% at 1000 Hz, is
varied from 5 V to 450,000 V.
Sensitivity
(S+N)/N on all channels shall be greater than 6 dB when the
RF level is 2 V (hard) modulated 30% at 1000 Hz at rated
audio.
Squelch
2 v 6 dB for 25 kHz channels.
3 v 6 dB for 8.33 kHz channels.
Selectivity
6 dB BW is greater than 8 kHz for 25 kHz channeling.
60 dB BW is less than ±25 kHz for 25 kHz channeling.
6 dB BW is greater than ±2.778 kHz for 8.33 kHz channeling.
60 dB BW is less than ±7.37 kHz for 8.33 kHz channeling.
Spurious Response Greater than 85 dB.
Modulation AM Double sided, Emission Designator 6K00A3E
Frequency Band
118.00 to 136.99 MHz
25 kHz and 8.33 kHz channel spacing
Transmitting Power
GNS 420W, GNS 430W
10 watts minimum, 15 watts maximum
GNS 420AW, GNS 430W
16 watts minimum, 20 watts maximum
Transmitter Duty Cycle Recommended 10% maximum.
Modulation Capability
The modulation is not less than 70% and not greater than
98% with a microphone input level of 70 mVrms to 3.0 Vrms.
Carrier Noise Level At least 45 dB (S+N)/N.
Frequency Stability 0.0005%
Demodulated Audio Distortion
Less than 10% distortion when the transmitter is modulated at
least 70%.
Sidetone
1.4 V
RMS
into a 500 load when the transmitter is modulated
at least 70%.
Demodulated Audio Response
Less than 6 dB when the audio input frequency is varied from
350 to 2500 Hz.
*
C37d Class 4 and 6 may not provide suitable COM transmit range for some high-altitude aircraft.
**Specifications shown apply at nominal input voltages of 13.75 VDC or 27.5 VDC, as applicable, and
with a nominal 50 ohm resistive load at the antenna connector.