Specifications

-4--7-
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.
Refer to Figure 1 or the top legend on the PC board. Install and solder
the following capacitors.
C1 .001mF (102) Discap
C2 .1mF (104) Discap
C3 .1mF (104) Discap
C4 10mF Lytic (see Figure 4)
C5 10mF Lytic (see Figure 4)
C6 10mF Lytic (see Figure 4)
C7 .1mF (104) Discap
C9 10mF Lytic (see Figure 4)
Install D2, the red LED. Cut two 7/16” plastic tubes
to be used as standoffs. Place each LED lead into
the tubing so that the LED stands 7/16” off of the PC
board. Look for the flat side at the base of the LED.
Mount it with the flat side as shown in Figure 1.
Solder into place.
Mount the switch 1/8” off of the PC board, as shown in Figure 5. Install
and solder the switch (S1) in the place shown in Figure 1.
Electrolytics have polarity.
Place the negative (–) lead in
the correct hole, as marked
on the PC board and part.
Mount the electrolytics so that
they lay on their side.
Figure 4
Install and solder the transistors with the flat side in the direction shown
in Figure 1.
Q1 - 5172
Q2 - 2N3904
Flat
Flat
Tubes
Install the probe tip. Cut a wire to 4 3/4”,
strip 1/4” of insulation off of both ends.
Solder one end to point P on the PC
board. Solder the other end of the wire
to the probe tip groove.
One of two types of jacks is supplied
in your kit. Look at the clip on the
jack for identification and wire
accordingly, as shown in Figure 5.
Cut two wires to 1 3/4” and strip 1/4”
of insulation off of both ends. Solder
the wires to the lugs of the jack
supplied as shown in Figure 5.
Solder the other ends of the wires to
the holes in the PC board marked
“EAR” as shown in Figure 5.
Clip
Clip
Figure 5
Mount switch 1/8” off
of the PC board.
1/8”