WhitakerAudio AM/FM Stereo Tuner 2012, Assembly & User Manual

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AM/FM Stereo Tuner
In the following steps, 4-pin Molex connectors will be used. After stripping the cable, place a
short (approximately 3/4-inch long) piece of heat-shrink tubing on each end of the shielded cable.
For the end of the cable inserted into the Molex connector, process (apply heat) after the wires
have been inserted into the connector but before the cable is installed in the tuner.
Hardware for the following steps can be found in the “4 Terminal Molex Housing and
Terminals” package.
Examine the Molex socket housing. The connector pins insert one way only. As each
connector pin is attached, check for a good crimp.
– Identify the AM Gain Control, R24 – 1 m
Ω
potentiometer , which is located on the AM
tuner PWB side of the chassis closest to the back panel. See the top chassis decal.
– Prepare an 18-inch long shielded cable. Attach Molex connector pins to each of the four
wires (including shield) on one end of the cable. Insert the connector pins into the socket
housing as follows: red to position #1, white to position #2, black to position #3, and
shield to position #4.
– Cut two short pieces of small heat-shrink tubing, each about 3/4-inch long. Place the
tubing at each end of the audio cable. Process.
– Insert the Molex socket into the Conn1 “Gain Control” connector on the AM tuner PWB.
Note that the drain wire goes to the last (ground) position.
– Route the cable to the rear of the chassis using the cable clamp located between the AM
tuner PWB and the side of the chassis.
– On R24, attach the wires from the cable as follows: black to terminal #1 (low), white to
terminal #2 (arm), and red to terminal #3 (high). Solder. Clip off the drain wire. it is not
used on this end. Dress the cable against the chassis.
Figure 5.10 Terminal numbering for chassis-mounted potentiometers.
Inside chassis view
Potentiometer
Term 1
(low side)
Term 2
(arm)
Term 3
(high side)