12 vocon rx audio, Vocon rx audio, 12 vocon rx audio—page 1 – Motorola SSETM 5000 User Manual

Page 122

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November 11, 2004

6881094C12-A

9-18

Troubleshooting Charts: VOCON RX Audio

9.12 VOCON RX Audio—Page 1

MAEPF-27394-B

Probe R406 for

Frame Sync Signal,

Compare with

RX SAP waveform,

Trace 1

Frame

Sync

Present?

Replace U401

and reflash

Probe R403 for
Data, Compare

with RX SAP

waveform, Trace 2

Signal

Present?

THD <3%?

Clock

Present?

Probe R405

for Clock Signal,

Compare with

RX SAP

waveform, Trace 3

Go to

RX RF

flowchart

Data

Present?

Check 

Distortion of

Signal at C533

Replace U501

(GCAP II)

Check Preamp

Input Signal at

C533  

No

No

No

No

No

Yes

Yes

Yes

Yes

1

Yes

Bad SINAD

Bad 20db Quieting

No Recovered Audio

Inject Standard

Input into Antenna

Connector

A standard input is an
RF signal with a 1 kHz
tone modulated with 3 kHz
deviation in a 25 kHz channel.

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