Motorola PDR 3500 Basic Service Manual page 43

9-14
If the station still does not generate rated power, suspect the
following:
- Power Amplifier Module failure
- Exciter Module failure
- Loose or faulty Exciter-to-PA RF cable
- Faulty forward voltage or control voltage
translation circuitry on backplane
Step 5. If the PA power out is okay, setup R2001 for
spectrum analyzer display. Press the PTT
button and observe the display. The display
should look similar to:
• If the display shows multiple carriers, evenly
spaced about the station transmit frequency,
suspect a faulty PA module.
• If the display shows a solid carrier, but off
frequency, suspect the following:
- Faulty Exciter or Station Control Module
• If the display shows a single carrier moving
erratically, suspect the following:
- Faulty Station Control Module
- Faulty Exciter Module
- Faulty PA Module
Step 6. If the display is okay, setup R2001 to display
modulation. Using the handset, push the PTT
button and speak into the mouthpiece. Verify
that the display shows:
• If the proper display is not obtained, suspect faulty
SCM or Exciter Module
Step 7. Set the R2001 for GEN/MON MTR. Press the PTT
button and speak loudly into the mouthpiece to cause
maximum deviation. Display should read ±5 kHz
maximum.
• If the proper display is not obtained, suspect faulty
SCM or Exciter Module
Step 8. This completes the Verifying Transmitter Circuitry
test procedure. If all displays and measurements are
correct, the transmitter circuitry may be considered to
be operating properly.
September 27, 2000 68P81093C75-O