User's Guide

Page 9
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Frequency response
25 kHz channel spacing The variation in frequency response with reference to a 1 kHz signal,
is within +1 dB and -2 dB across the frequency range 300 to 3400 Hz.
The response is less than -20 dB for frequencies at or below 100 Hz,
and less than -30 dB at 4 kHz and above.
8.33 kHz channel spacing The variation in frequency response with reference to a 1 kHz signal,
is within +1 dB and -2 dB across the frequency range 350 to 2500 Hz.
The response is less than -10 dB for frequencies at or below 100 Hz,
and less than -30 dB at 4 kHz and above.
Distortion
25 kHz channel spacing For RF input signals between -53 dBm and +10 dBm, the total
harmonic distortion is less than 5% within the frequency range 300 Hz
to 3.4 kHz when the modulation depth is between 30 and 90%.
8.33 kHz channel spacing For RF input signals between -53 dBm and +10 dBm, the total
harmonic distortion is less than 5% within the frequency range 350 Hz
to 2.5 kHz when the modulation depth is between 30 and 90%.
Wanted Signal Dynamic Range (RF AGC)
For a 90% modulated on-channel signal, a change in signal level from
-107 dBm to +10 dBm results in less than a 3 dB change in audio
output. On-channel signals modulated at 90% up to a level of
+17 dBm achieve at least 10 dB SINAD.
Audio AGC
AM-Voice Mode The audio AGC compresses a 30% to 90% variation in input
modulation depth to an audio output power change of 1 dB or less.
The audio output level is maintained at the equivalent of 90%
modulation. Audio AGC can be disabled.
AM-MSK Mode The audio AGC is permanently disabled.
Squelch
The transceiver has a noise compensated carrier operated squelch
with an adjustment range of -114 to -60 dBm, and providing greater
than 60 dB of quieting. Note that when the RF pre-attenuator is
switched in, the adjustment levels are increased by 6 dB.
The squelch has a noise compensation disable facility to provide
carrier only operation.
Transceiver Tx Control
Transceiver Tx control characteristics are as follows:
Audio Inputs
AM-MSK AM-MSK data is connected to the transceiver via an external modem
connected to the line inputs.