Front End Filter Alignment; Figure 6-25. Front End Filter Alignment Screen (Uhf1) - Motorola APX 3000 Basic Service Manual

6-20
6.6

Front End Filter Alignment

The alignment procedure adjusts the front end receiver bandpass filters for the best receiver
sensitivity and selectivity. This procedure should be performed for all test frequencies to allow for
proper software interpolation of frequencies between the test frequencies in the band
(see Figure 6-25
NOTE: Rx Front End Filter Alignment is required after replacing (or servicing) the transceiver board.
6.6.1 Procedure for UHF 1 (Auto Tune)
Tuning of the radio is done through Rx Front End Filter tuning screen
1. Select the Rx Front End Filter alignment screen. See
2. Click on the slider or the "New Softpot Value" text box to select which frequency to tune.
3. Apply RF test signal input with no modulation at -90 dBm on the Test Signal Frequency
displayed at the top of the screen.
4. Left-click the Autotune button.
5. Repeat the steps 2 to 4 for all frequencies.
6. Left-click the Program All button on the screen to save the tuned values in the radio.
6.6.2 Procedure for UHF 2 (Auto Tune)
Tuning of the radio is done through Rx Front End Filter tuning screen
1. Select the Rx Front End Filter alignment screen. See
This procedure should only be attempted by qualified service
technicians.
and Figure 6-26).

Figure 6-25. Front End Filter Alignment Screen (UHF1)

Radio Alignment Procedures: Front End Filter Alignment
Notes
Figure
Figure
6-25.
6-26.