Motorola GP series Service Information

Troubleshooting Flow Chart for Receiver, for models with PCB 8486473Z04 (Sheet 1 of 2) 3-3
2.0 Troubleshooting Flow Chart for Receiver, for models with PCB
8486473Z04 (Sheet 1 of 2)
Bad SINAD
Bad 20dB Quieting
No Recovered Audio
START
Audio at pin
8 of U3220?
Check Controller
(in the case of no audio)
OR ELSE go to “B”
Yes
No
Spray or inject 44.85MHz
into XTAL Filter Y3200
Audio heard?
B
Yes
No
Check 2nd LO
(44.395MHz) at C3274
LO Present?
B
Yes
Voltages
ok?
Biasing ok?
Check circuitry
around U3220.
Replace U3220
if defect
No
No
A
Yes
Check Q3200 bias
for faults.
Replace Q3200.
Go to B
Yes
No
Check voltages on
U3220
Check circuitry
around Y3202.
Replace Y3202
if defect

Motorola GP series Specifications

General

Operating Temperature	-30°C to +60°C
Frequency Range	136-174 MHz
Number of Channels	16
Channel Spacing	12.5 kHz / 25 kHz
Battery Life	8 hours (with standard battery)
Operating Voltage	7.5V DC
Ingress Protection	IP54
MIL-STD	810 C, D, E, F