Motorola GP2000 Service Manual

Troubleshooting charts Section 7 -27
6.0 Troubleshooting charts
Start
Very low or no 12
dB SINAD
Noise at spkr
when radio is
unsquÕd?
Is 1st LO at
TP302 >0
dBm?
Inject on channel
signal at RF port,
L706 pin 6
Is 12 dB SINAD
-110 dBm?
Inject 45.1
MHz signal at
Is 12 dBS -117
dBm?
Inject a 45.1
MHz signal at
C501
Is 12 dBS -110
dBm?
1
Check IFIC
Q506 (see
below)
Noise at pin 9
of IFIC Q506?
Check
VCO/Synth
Inject on
channel signal
at C407
Check
harmonic
filter and
antenna path
Check external
components
connected to IFIC. If
OK, replace Q506
Check mixer,
Q407
Is Q506 biased
correctly?
Check XTAL
filter X501
Check +5vRX
and IF amp
components
Is 12 dBS -116
dBm?
Check Q702
Is Q404 biased
properly?
Check 2-pole and
RF BPF
components
Check +5vRX and
Q404 bias circuitry
1
Is 2nd LO on
freq?
Check VDC of
all IFIC pins
Are VDC of
pin 4 and
10 of IFIC
OK?
Are voltages on
pins OK?
Check 2nd LO
XTAL and
components
Check IFIC
(see below)
Check external
components
connected to IFIC
NO
NO
YES
YES
NO
YES
YES
NO
YES
NO
YES
YES
NO
YES
NO
NO
YES
YES
NO
YES
YES
NO
NO
NO
R459 Terminal
Troubleshooting Flow Chart for
Receiver

Motorola GP2000 Specifications

General

Brand	Motorola
Model	GP2000
Category	Portable Radio
Language	English