Receiver Troubleshooting; Table 7-2. Receiver Troubleshooting Chart - Motorola PM1200 Basic Service Manual

Basic Troubleshooting: Receiver Troubleshooting
7.5

Receiver Troubleshooting

Table 7-2 can help troubleshoot problems that might occur in the receiver section of your radio.
Symptom
Radio does not
power-up
No Receiver
Audio or
Receive Does
Not Unsquelch
Audio Distorted
or Not Loud
Enough
RF Sensitivity
Poor
Radio Will Not
Squelch
Excessive
Noise in Fading
Conditions
6880309U09-A

Table 7-2. Receiver Troubleshooting Chart

Possible Cause
Blown power fuse
RF deck
Control Head / RF deck
flex
Code Plug
Speaker
Codeplug
Synthesizer Not On
Frequency/Working
Synthesizer Not On
Frequency/Working
Codeplug
Check Programming for
Correct Bandwidth
Correction or Test (Measurements Taken at
Room Temperature)
Check the fuse in the DC cable.
Measure the voltage of MAIN UNIT J1001. The
voltage from a battery is applied all the time in this
part (+B).
If +B is low, check the P7001 (DC Connector) and
DC cable.
If +B is not present on J5006 pin 12, then the flex is
suspected. Replace the flex.
Check the codeplug to ensure correct frequency
and signaling (PL, DPL) is enabled by using CPS.
Check for speaker leads shorted to ground or open
speaker wires. Replace, if necessary.
Ensure the codeplug is properly configured,
including bandwidth and signaling.
Check the local oscillator frequency.
Check the local oscillator frequency.
Check the offending channel for spurious activity by
benchmarking with a known-good radio or service
monitor.
If not, increase the squelch level using the
appropriate radio-programming software.
Reprogram the codeplug with the correct
bandwidth.
7-3
October 26, 2007