Motorola HT1250-LS+ - Page 46

4-10 Maintenance
IF Signal at
C3281?
No
RF Signal at
T3301?
RF Signal at
C3353?
No
RF Signal at
C3346?
No
RF Signal at
C3341?
No or
Check harmonic filter L3531 & L3532,
C3532 and ant. switches D3521,
D3551, L3551 & associated compo-
nents.
Check filter between
C3341 & Q3302
Inject RF into J3501
No
Ye s
Check RF amp (Q3302)
Stage.
Check filter between
Q3302 & T3301
Ye s
Check T3301, T3302,
CR3301
Ye s
1st LO
O/P OK? (+5
dBm at T3302
Pin 6?)
Locked?
Ye s
Check FGU
Ye s
Trace IF signal
from C3200 to
Q3200. Check for
bad XTAL filter.
No
Ye s
Q3200 collec-
tor OK?
IF signal
present?
Before replac-
ing U3101,
check U3101
voltages; trace
IF signal path
Ye s
Check
for 2.9 VDC
@ Q3200-C
Is 5V supply
present?
Check U3711
No
No
No
Ye s
Ye s
A
A
B
weak RF
Troubleshooting Flow Chart for Receiver (Sheet 2 of 2)