Rx Back-End-Poor Sinad Or No Audio (700-800 Mhz)-Part 3 Of 3 - Motorola ASTRO XTL 1500 Detailed Service Manual

Troubleshooting Charts: Flowcharts
5.6.38 RX Back-End—Poor SINAD or No Audio (700–800 MHz)—Part 3 of 3
Inspect solder on U6000
and supporting circuitry,
look for missing or
misplaced components
Visual
inspection
OK?
Replace
U6000
Figure 5-38. RX Back-End—Poor SINAD or No Audio (700–800 MHz)—Part 3 of 3
6815854H01-A
2
Measure DC
tuning voltage
(Vt) at R6007
Freq of
No
CLKOUT
<1.2MHz?
Yes
DC
No
voltage at
R6007 =
3.0V?
Yes
and/or missing components
3
Repair defects
No
and/or replace
suspect components
Yes
DC
No
voltage at
R6007 =
0.0V?
Yes
3
Inspect clock oscillator
circuit for solder defects
Visual
No
inspection
OK?
Yes
Replace
varacter diode
D6030
MAEPF-27808-O
3
Repair defects
and/or replace
suspect components
June 15, 2005
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