6881076C20-E February 3, 2003
Basic Troubleshooting: Transmitter Troubleshooting 9-5
9.4.2 ASTRO Digital Spectra Plus
9.5 Transmitter Troubleshooting
The following table can help you troubleshoot problems that might occur in the transmitter section of 
your radio.
Table 9-4.  ASTRO Digital Spectra Plus Operational Error Codes
Error Code Description
Error 
Type
Corrective Action
FAIL 001 Synthesizer Out-of-Lock NON-
FATAL
1. Reprogram codeplug
2. Replace RF board.
FAIL 002 Personality checksum or 
system block error
NON-
FATAL
Reprogram codeplug.
Table 9-5.  Transmitter Troubleshooting Chart
Symptom Possible Cause
Correction or Test (Measurements 
Taken at Room Temperature)
No RF Power 
Output
TX Power Level 
Programming
Check TX power level programming (from 
the appropriate radio programming 
software).
No Keyed 9.4 Vdc from 
Command Board
Check for keyed 9.4 Vdc on J500 pin 15 
with transmitter keyed.
If none, replace the command board.
No Injection to Power 
Amplifier
1. Check the lock line (J500 pin 14). If not 
less than 2 Vdc, go to the Synthesizer 
Troubleshooting Chart on 
page 9-12.
2. Measure injection, which should be
> +18 dBm.
If low, replace the VCO board.
Power Amplifier Measure PA control voltage (P503 pin 2).
If >6 Vdc, replace the PA board.
Power Control Circuit If PA control voltage above was
<6 Volts, replace the command board.