Synthesizer - Motorola GTX/LCS 2000 Service Manual

Yes
Check
controller
circuit.
NOTE:
RF input level is -47dBm.
All the levels indicated have
a tolerance of ±10%.
Is <-35dBm
Yes
Check
present on
Y5201.
Y5201-3?
Is <-20dBm
Yes
Check
prsent on
Q5201.
Y5202-1?
Yes Is <-22dBm
Check
present on
Y5202.
Y5202-3?
Troubleshooting Flow Chart
for Receiver
8-2 Troubleshooting
Start
Is AUDIO_DET No
AC level
0.2Vrms,
1KHz?
Is
RF_REG_5V
present at
Q5320 E-2?
Is K9.1 at
TP10 at 0V?
Check RX_INJ
level.
Check LO_INJ
level.
>-35dBm
Check IF
level
on L5401.
No
No
Yes
45.1MHz, present
No
Replace
B
U5211.
No
Check
DC circuit.
Yes
No
Check
logic circuit.
Yes
<-
50dBm
Check
Rx/Tx switch.
>-50dBm
Check
<0dBm

synthesizer

Circuit.
>0dBm
<-35dBm
No
Is <-38dBm
present at
C5312?
Is <-48dBm,
No
at U5211-5?
End
Yes
Is DC
Yes No
at R5302
O.K.?
Replace Replace
R5302.
Q5301.