38
Front-End Filter
Alignment (VHF
and UHF)
From the MAIN MENU, press F2, F3 and then F2 to access this screen.
This alignment procedure is required every time the RF Board is replaced or
serviced. This alignment adjusts the corner frequencies of an RF front-
end bandpass filter. It needs to be performed at multiple frequencies to
allow for proper alignment across the entire RF band. The RF band is
divided into frequency zones with a calibration point (value) in each
zone.
The test frequencies and current values are displayed on the left side
of the screen. On the right side of the screen, the front-end filter
softpot values are displayed. A bar at the bottom of the screen shows
the current setting in relation to the minimum and maximum
settings.
Refer to your Radio Service Manual for the Front-End Filter Alignment
(UHF and VHF) procedure.
Programming Procedure 1. Apply the appropriate RF signal to the radio.
2. Modify the Rx Front End Filter Softpot setting using the UP/
DOWN arrow keys.
3. Use the Tab key to move between frequency points.
4. Press F8 to save the new values.
BCC
MOTOROLA Radio Service Software Use <: or <SHIFT><<SHIFT>: to change
HT/JT1000/VISAR Model: and <ENTER> to go to next softpot.
Serial:
SERVICE:RCVR ALIGN:FE FL
Front End Filter Alignment
--------------------------
Test Current
Frequency Value New Softpot Value
450.02500 92 92
465.22500 105 105
475.22500 122 122
484.97500 138 138
500.27500 156 156
511.97500 177 177
519.97500 191 191
0 255
MIN |----+----+---X-+----+----+----+----+----+----+----+----+----| MAX
F1 F2 F3 F4 F5 F6 F7 F8 F9 F10
HELP PROGRAM EXIT
VALUE
!
Caution
These procedures should be attempted only by
qualified service personnel. Failure to perform
alignment procedures properly may result in seriously
degraded radio or system performance.
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