Motorola LB3 (42.0 - 50.0MHz) 서비스 정보 - 페이지 18
{카테고리_이름} Motorola LB3 (42.0 - 50.0MHz)에 대한 서비스 정보을 온라인으로 검색하거나 PDF를 다운로드하세요. Motorola LB3 (42.0 - 50.0MHz) 26 페이지. Gm series professional radio
페이지 인쇄
3-2
2.0
Troubleshooting Flow Chart for Receiver
(Sheet 1 of 2)
B
B
Check
circuitry
around
U1103.
Replace
U1103 if
defect.
START
Bad SINAD
Bad 20dB Quieting
No Recovered Audio
Audio
at pin 8 of
U1103
?
No
Spray or inject 10.7MHz
into XTAL Filter FL1102.
Yes
Audio
heard
?
No
Check 2nd LO
(10.245MHz) at C1129.
Yes
LO
present
No
Check
No
voltages on
U1103.
OK?
Yes
Check circuitry around Y1101.
Replace Y1101 if defect.
Check Controller (in the case of no audio).
Yes
Replace Q1106.
Low Band TROUBLESHOOTING CHARTS
Or else go to "B"
A
Check Q1106 bias
for faults.
Biasing
OK
No
Yes
Go to B