Troubleshooting - Radio Shack PRO-60 Service Manual

TROUBLESHOOTING
5ymptom
Possible CauselRemedy
Display does not light and no sound comes out • Detective batteries:
when power is on
Replace.
Volume control: Maximum (MAX) • Wrong polarity ot batteries:
Squelch control: Counterclockwise (CCW).
Correct the polarity ot batte ries.
• Detective power jack or charge jack:
Replace.
• Detective ON/OFF switch on volume control:
Replace.
Display lights but there is no sound • Detective speaker or headphone jack:
Volume control: MAX
Replace.
Squelch control: CCW • Detective audio amplitier circuit (IC306) and/or associated
circuit
Replace the detective components.
• Detective IF amplitier (IC301) and/or associated circuit
Replace the detective components.
• Detective squelch control (VR301 ) and/or associated
circuit
Replace the detective components.
• Detective AF pre-amp circuit (0307) and/or associated circuit
Replace the detective components.
• Detective audio mute switching circuit (0308) and/or
associated circuit
Replace the detective components.
• Detective switching circuit (IC303) and/or associated circuit
Replace the detective components.
Sound comes out but display does not light • Detective LCD or rubber connector:
Volume control: MAX
Replace the detective components.
Squelch control. CCW • Detective CPU (IC1):
Replace IC1.
Does not scan and squelch does not operate • Detective IC301 or IC302 squelch control terminal:
Replace IC301 or /C302.
Does not scan but squelch operates • Detective CPU (IC1):
Replace IC 1.
Shows correct display at the time
ot • Detective CPU (IC1) and/or associated circuit
programming, but after scanning, shows taulty
Replace the detective components.
display
Sound does not come out in NFM mode but
• Detective IC1:
AM and WFM operate Replace.
• Detective control circuit (IC303, IC30S) and/or associated
circuit
Replace the detective components.
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