Motorola MTX series Theory/Troubleshooting Manual

38
TROUBLESHOOTING FLOW CHART #3A
(VHF/UHF DC Switch)
No R5
Q105 Pin 2
Voltage
at Q105
Pin 3?
Voltage
at U103,
Pin 3?
Voltage
at Q107,
Pin 2?
Voltage
at Q107,
Pin 3?
Voltage
at Q107,
Pin 4?
7.5V at
U202
Pin 8?
5V at
U102
Pin 1?
Less than
4.8V at Q105
Pin 1?
Replace
Q105
Replace
U103
Check Power
Supply
Replace
Q107
Check L131,
L121 and CR109
and L122 For
Open Connections
YES
YES
YES
YES
YES
YES
NO
YES
NO
NO
NO
YES
NO
NO
NO
Replace
U102
Replace
U202
MAEPF-23270-O
No T5
Voltage
at Q104
Pin 3?
Voltage
at U202,
Pin 8?
Replace
U102
Go to
Controller
Troubleshooting
Chart #8A
Replace
U202
Check Fuse,
Flex Connection
J301-1, 2, 20;
Volume Switch
Less than
4.8V at Q104
Pin 1?
5V at
U102
Pin 1?
Voltage
at U202
Pin 8?
Check
Interconnect
Flex P301,
Good?
5V at
Pin 3
of U102?
Replace U202
Rectify
Fault
ISS.
REVISION
RLSE. RLSE.
LETTERING SIZE:
REQUIRES:
O
Replace
Q104
YES
NO
MAEPF O
YES
YES
NO
YES
YES
NO
NO
NO
NO
NO
YES
YES
SW
3/31/93
JWB
3/31/93

Motorola MTX series Specifications

General

Brand	Motorola
Model	MTX series
Category	Portable Radio
Language	English