Motorola MTX series Theory/Troubleshooting Manual

35
TROUBLESHOOTING FLOW CHART #1B
(800/900MHz Transmitter RF)
MAEPF-23441-O
REQUIRES:
O
JEDI
Troubleshooting Chart
ISS.
CORRECTED
AS
MARKED
ILLUSTRATOR DATEENGINEERDATE PROGRAM D
DESCRIPTION
TECHNICAL PUB
DWG. NO.
LETTERING SIZE:
EDITOR DATECHECKERDATE
Illustrator
M
SW
3/12/93
3/31/93
JWB
C
No/Low Power
Replace
Ant Contact
YES
NO
Check
Continuity at
Ant. Cont.
NOBADBADGOOD
GOOD GOOD
BAD
Replace S101 Replace U104
Go to VCO
Chart #5B
Go to DC Switch
Chart #3B
NO
YES
Check E101,
E102, P404
Check Q101
& R129
Go to VCO
Chart #5B
Replace U105
Check R101,
R103
NO
YES
YES
NO
NO
YES
NO
YES NO
YES YES YES
NONO
YES YES
NO
NO
NO
GOOD
YES
NO
Check U102
D/A IC
VDC
U105-2, 5
0.37 VDC
U101-12
VDC
U105-1
VDC
U105-3, 4
VDC
Base Q110
VDC
U105-7
VDC
U101-21
VDC
U101-2
VDC
U102-11
Check: U104,
CR101, R114,
C121, R110,
R111
OHM\
Q110
VDC
U101-7
Check U101
ALC IC
Check U102
D/A IC
VDC
at
Q108-2
RF
Input Drive
U105-1
>1dB
B+ VDC
U105-6
Check Continuity
Between U101-13
& P404-1
Change ALC
U101
YES
YES
NO
See Chart #4
Check D/A
Chec R113
YES
YES
NO
NO
NO
5 VDC
U101-11
VDC
Lock Det
Cath.
CR103
VDC
U102-3
VDC
U101-13
Check
S101
Check
Continuity
across
U104
RF
Input Drive
U105-1
>1dBm
TX
Current
>500 mA
YES
NO
Check
L105

Motorola MTX series Specifications

General

Brand	Motorola
Model	MTX series
Category	Portable Radio
Language	English