Front End Filter Alignment; Definition; Procedure For Vhf - Motorola ASTRO XTSTM 2500 Basic Service Manual

Front End Filter
Alignment

Definition

Procedure for VHF

6. Repeat the above process for all frequencies.
7. Left-click the Program All button on the screen to dekey the radio and save
the tuned values.
8. Left-click the Close button on the screen to return to the Transmitter
Alignments menu.
Refer to your Radio Service Manual for alignment procedure
details. This procedure should only be attempted by qualified
service personnel.
C a u t i o n
This alignment procedure adjusts the front end receiver bandpass filters for best
receiver sensitivity and selectivity. It should be performed for all test frequencies to
allow for proper software interpolation for frequencies in between the test
frequencies in the band (see Figure 12).
NOTE: Rx Front End Filter Alignment is required after replacing (or
servicing) the transceiver board.
1. Left-click the desired frequency field.
2. Apply an RF signal with no modulation at -90 dBm on the current operating
frequency.
3. Adjust the softpot value until the maximum RSSI value is found.
Radio Alignment Procedures
31