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Testing the Signal Tracer
Checking out your signal tracer is fairly easy. You will need a DC voltage
source of between 5 to 40V. A 9V battery will do fine. Connect the red
alligator clip lead to the positive voltage and the black lead to the negative
voltage. The red LED should light up. Next, clip the green lead to the
probe tip and connect the earphone to the jack. You should hear a tone
in the earphone.
Vary the gain control and the tone should vary in
amplitude.
Obtain an audio amplifier or an AM radio. Make sure the amplifier or radio
is isolated from the power line. Set the probe slide switch into the tip inject
position. Connect the green lead to the output of the amplifier or radio
speaker. Touch the probe tip to the input of the last stage of the amplifier.
The tone should be heard in the earphone or speaker of the radio.
Continue injection by moving the tip toward the input and output of each
stage. Vary the probe gain to prevent overload of the probe. If you have
an AM radio, try injecting the signal into the IF and RF stages. The signal
tracer produces a 1kHz harmonics which extend into the frequencies of
the AM radio, and you will be able to hear these harmonics as 1kHz
detected signals.
At times, it may be advantageous to reverse the process. Move the switch
to the tip receiver position. Now, connect the green lead to the input of
the amplifier. The probe tip now is used to pickup the signal. Start with
the first stage and continue to the last. This method is helpful if the last
stage of the amplifier is defective.
Should your signal tracer fail to perform as expected, refer to the
troubleshooting guide for help in solving the problem.
