Service Manual

Page 5.8
6 ~ CIRCUIT DIAGRAMS
5.2.3.3 Rx Front End
1. Ensure that the TCX0 Alignment has been done before proceeding with this section.
2.
Select the
Rx Front End
Page
3.
Select
Open Mute
.
4.
Set the
Volume
slider to 15.
Speaker audio should now be visible on the Scope. If required readjust the
Volume
slider to a suitable
level.
5. Set the Signal Generator to the Channel 0 carrier frequency, with a 1000Hz modulation signal, a
deviation of ±2 kHz and an RF level of -90dBm.
6.
Select
Channel 0.
7.
Select
Auto Align
.
The front end will be tuned automatically and finish with an RSSI reading of typically around 150.
8. Repeat Steps 7 to 8 for the remaining 3 Channels (1, 2, & 3).
9. Change deviation to 1.5kHz.
10. Verify that the receiver sensitivity is better than -117.5dBm for 12dB SINAD on all channels.
(Sensitivity is typically -120dBm).