Motorola VRS750 Service Manual page 77

STEP 2
STEP 3
****** If a failure occurs, go to STEP 3 otherwise proceed
9. Press Toggle Bias again to disable the PA Bias softpot.
10. Program the Bias softpot into the radio's codeplug via pressing
Program.
11. Exit the PA Bias Low Power function.
1. Increase Y until Y-X is within the range given for PA current in
Table 14 (STEP 2).
2. Press Toggle Voltage again to disable the PA control voltage edit
box/spin control.
3. Press Toggle Bias in order to enable the PA Bias softpot.
4. Increase the softpot value to obtain Z until Z-Y is within the
range for Bias Current as indicated in Table 14 (STEP 2).
****** If a failure occurs, go to STEP 3 otherwise proceed
5. Press Toggle Bias again to disable the PA Bias softpot.
6. Program the Bias softpot into the radio's codeplug via pressing
Program.
7. Exit the PA Bias Low Power function.
1. Press Toggle Bias twice to reset the softpot value.
2. Press Toggle Bias again to disable the PA Bias softpot.
3. Measure/read the dc current drawn from radio (specifications will
vary from radio to radio). Call this X. This value should typically
range from 70-100 mA or 0.07-0.1 A.
4. Press Toggle Voltage to enable the PA control voltage edit box/
spin control.
5. Increase the Voltage softpot value and measure/read from current
meter. Call the new value Y.
6. Increase Y until Y-X is within the range given for PA current in
Table 14 (STEP 3).
7. Press Toggle Voltage again to disable the PA control voltage edit
box/spin control.
8. Press Toggle Bias in order to enable the PA Bias softpot.
9. Increase the softpot value to obtain Z until Z-Y is within the
range for Bias Current as indicated in Table 14 (STEP 3).
Table 14. PA Bias Low Power Specification for VRS750s (UHF Only)
Step
STEP 1
STEP 2
STEP 3
PA Current (mA) Bias Current (mA)
20-30
30-45
40-55
630-750
750-900
600-750
65