Service Instructions
Item 9: Receiver Sensitivity
Purpose:
Checking the receiver sensitivity
Test method:
Radio test set in RX mode
Input signal:
Apply an RF signal at low, mid, and high channel modulated with a 1kHz tone at
5.7kHz deviation at a level of -113dBm to the antenna input
Measurement point:
At the AFMS output from the system connector measured with an AC volt meter
Limit:
Better than 20dB SINAD at low, mid, and high channel
Procedure:
1. Select channel (TP-1:1329, 1, or 600)
2. Disable AFC (TP-15:0)
3. Turn the transmitter on (TP-2:2)
4. Apply an RF signal at low, mid, and high channel modulated with a 1kHz tone at
5.7kHz deviation at a level of -113dBm to the antenna input
5. Measure better than 20dB SINAD on AFMS using a CCITT filter
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