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TROUBLESHOOTING TIPS
PROBLEM: Very little noise from the speaker when adjusting the coils.
Adjusting has little effect.
SOLUTION: Check Y2 for proper frequency, and then check TP4 for about 0.4
volts then channel 1 is selected (see step 6 of initial testing). If you don't have
either of these, your problem lies in the PLL not operating as it should. Check
around the local area using your parts list and schematic as a guide. We bet
you will find a cold solder joint or a solder bridge somewhere. Also check
alignment of D1, the varactor diode. This part will definitely cause this problem if
put in backwards.
PROBLEM: The unit doesn't scan channels, and doesn't skip channels when I
press the switches.
SOLUTION: Your microprocessor is brainless. Actually it appears that the
microprocessor is not running as it should. Check R35 and C52. Use a high
impedance or 10x probe on a scope or frequency counter to verify that there
are oscillations on those pins. If so, check to make sure all pins are mounted in
the socket. Many fine technicians get stumped by the problem of a pin not
inserted into an IC socket properly.
PROBLEM: Nothing! Nada! Nothing is working at all.
SOLUTION: Check your power source first. Make sure the center lug of the
power jack is positive, and the outside is negative. Also verify that you have
voltage on either outside pin of the voltage regulator. There should be 12 volts
on one and five volts on the other. If you have 12 volts on one and nothing on
the other, turn off your power supply and check through your circuit for a likely
solder bridge acting as a short.
PROBLEM: Power supply shorts out when I turn on the power.
SOLUTION: You either have a short circuit on your PC board or you are using
an antenna that acts as a short with DC. To check your antenna, unhook it from
the radio and measure its resistance with an ohm meter. The antenna should
read an open without a preamp, or a high resistance (>470 ohms) with a
preamp. If you want to use an antenna that acts as a short, you will need to
remove L1, the 2.2uH coil, then power your preamp separately.
PROBLEM: I just can't get the #@%*$#&! thing to work! It's Ramsey's fault!
SOLUTION: Read the warranty information towards the back of this manual.
WSR-1A• 25
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