Vocon Rx Audio—Page 1 - Motorola ASTRO XTS 5000 Detailed Service Manual

6-18
6.19 VOCON RX Audio—Page 1
Bad SINAD
Bad 20db Quieting
No Recovered Audio
Inject Standard
Input into Antenna
Connector
Check Preamp
Input Signal at
C533
No
Signal
Present?
Yes
Check
Distortion of
Signal at C533
No
THD <3%?
Yes
1
April 15, 2002
A standard input is an
RF signal with a 1 kHz
tone modulated with 3 kHz
deviation in a 25 kHz channel.
Probe R403 for
Data, Compare
with RX SAP
waveform, Trace 2
Replace U501
Troubleshooting Charts: VOCON RX Audio—Page 1
Probe R405
for Clock Signal,
No
Data
Compare with
Present?
RX SAP
waveform, Trace 3
Yes
(GCAP II)
Go to
RX RF
flowchart
No
Clock
Present?
Yes
Probe R406 for
Frame Sync Signal,
Compare with
RX SAP waveform,
Trace 1
Frame
Yes
Sync
Present?
No
Replace U301
(FLIPPER)
MAEPF-27394-O
68P81094C31-O