WhitakerAudio J C Whitaker 20 W Stereo Audio Amplifier, Manual

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Connect the other lead to the Hot-6 post on Amplifier PWB #1. Orient the device so it is
horizontal.
– Prepare a 24-inch long #18 white wire. Install a quick-disconnect terminal to one end of
the wire. Attach to the N-5 post on the Amplifier PWB #1 (right channel) board.
– Prepare a 24-inch long #18 black wire. Install a quick-disconnect terminal to one end of
the wire. Attach to the Hot-7 post on the Amplifier PWB #1 (right channel) board.
– Twist the white and black wires just prepared along their length and route to the side of the
chassis that will hold the preamplifier power supply PWB using the available cable
clamps. The free ends of this cable will be connected later during installation of the
preamplifier power supply PWB.
The primary power connections have now been made. Recheck your work. The chassis at this
stage of assembly is shown in Figure 5.12.
5.6.10 Chassis-Mounted Control
In the following steps, the Hum Balance potentiometer will be connected. Terminal numbering
for the chassis-mounted potentiometer is shown in Figure 5.13.
– Prepare two 16-inch long #22 wires, one brown and one green. Twist along the length of
the wires, leaving about 2-inches free on each end. Attach quick-disconnect terminals to
each wire at one end.
– Connect the brown wire terminal to the R55a post on the left channel PWB.
– Connect the green wire terminal to the R55b post on the left channel PWB.
– Using the available cable clamp, route the green/brown twisted pair to Hum Balance
control R55, which is located at the rear of the chassis, adjacent to the back panel. Trim
the wire lengths if needed. Slip a short piece of small heat shrink tubing onto each wire.
Secure the brown wire to terminal #1 of R55 . Solder in place. Secure the green wire to
terminal #3 of R55 . Solder in place. Process (heat) the tubing.
– Prepare a 16-inch long #22 orange hookup wire. Install a quick-disconnect connector on
one end of the wire. Attach to the R55arm post on the left channel PWB. Route the other
end of the wire through the available cable clamp to R55 at the rear of the chassis. Trim