Realistic PRO-2021 - Band-Specific Operational Failures; Search Functionality Issues

7) Display lights but PROGRAM does
not operate.
8) Low (Mid) band does not operate
but Air, High and UHF operates.
9) Air band does not operate but
Low, High and UHF operate.
10) High band does not operate but
Low and UHF operate.
11) UHF band does not operate but
Air, High and Low operate.
12) Air, Hiah and UHF band do not
operate but Low operates.
13) АН bands do not operate but
display OK.
14) Searches but does not halt on
the correct freguency.
Cause/Remedy
Defective Keyboard or connector and/or associated circuit components:
@ Replace the defective parts.
1) Defective Low band RF Coils T-3, 6 and/or VCO circuit components:
e Replace the defective parts.
2) Defective band switch circuit components:
@ Replace the defective parts.
Defective AM IF Amp Q15, 16 and/or associated circuit components:
е Repiace the defective parts.
1) Defective Air and High band RF Coils T1,2,4,5 and/or associated
circuit components:
@ Replace the defective parts.
2) Defective band switch circuit components:
@ Replace the defective parts.
1) Defective UHF band RF amplifier Q4, mixer Q5, multiplier and/or
associated circuit components:
@ Replace the defective parts.
2) Defective band switch circuit components:
е Replace the defective parts.
Defective VCO circuit 08, D16 and/or associated circuit components:
e Replace the' defective parts.
1) Defective PLL circuit IC1, 7 and/or associated circuit components:
е Replace the defective parts.
2) Defective ІС-4 and/or associated circuit components:
€ Replace the defective parts.
1) Defective 021, 1C-6 and/or associated circuit components:
€ Replace the defective parts.
2) Discriminator Coil T10 is out of adjustment:
e TP3 shall have 1/2 VCC (approx. 2.8V) in normal receiving mode.
3) 15 50.700 MHz adjusted correctly?:
€ Refer to page 9 REFERENCE FREQUENCY OSC ALIGNMENT.
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