Front-End Filter Alignment (Vhf And Uhf) - Motorola HT 1000 User Manual

Front-End Filter
Alignment (VHF
and UHF)
BCC
Programming Procedure
38
From the MAIN MENU, press F2, F3 and then F2 to access this screen.
MOTOROLA Radio Service Software
HT/JT1000/VISAR Model:
Serial:
SERVICE:RCVR ALIGN:FE FL
Test
Frequency
450.02500
465.22500
475.22500
484.97500
500.27500
511.97500
519.97500
0
MIN |----+----+---X-+----+----+----+----+----+----+----+----+----| MAX
F1 F2 F3
HELP
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.
These procedures should be attempted only by
!
qualified service personnel. Failure to perform
alignment procedures properly may result in seriously
Caution
degraded radio or system performance.
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.
Use <: or <SHIFT><<SHIFT>: to change
and <ENTER> to go to next softpot.
Front End Filter Alignment
--------------------------
Current
Value New Softpot Value
92
105
122
138
156
177
191
F4 F5 F6 F7
92
105
122
138
156
177
191
255
F8 F9 F10
PROGRAM EXIT
VALUE