WhitakerAudio J C Whitaker 20 W Stereo Audio Amplifier, Manual

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– Prepare an 18-inch long #22 yellow wire. Attach a quick-disconnect terminal to one end.
Attach to the 5Vdc post on the left channel PWB. Route the free end to the front panel
using one of the available cable clamps. Connect the wire to one of the terminals on the
Speaker On-Off switch, SW52. Do not solder.
– Prepare a 16-inch long #22 yellow wire. Connect one end of the wire to the available
terminal on the front panel Speaker On/Off switch, SW52. Do not solder.
– Install VR55 – 18 V varistor. Connect one lead to each terminal on the front panel Speaker
On.Off switch, SW52. Solder (2 wires per terminal.) It may be helpful to use a short piece
of spaghetti on each lead.
– Dress the wiring against the chassis. Route the free end of the yellow wire to the back
panel through the cable clamp adjacent to the right channel PWB. It will be connected
later.
– Prepare a 19-inch long #22 yellow wire. Attach a quick-disconnect terminal to one end.
Attach to the GND post on the left channel PWB that is next to the 5Vdc post. Route the
free end to the back panel using one of the available cable clamps. The wire will be
connected later.
5.6.11.1 Output Transformer Secondary Connections
Examine the secondary leads from the two output transformers. There are four wires from each
device. Black is common and the other three leads provide for 4, 8, or 16 Ω outputs. In order to
optimize the amplifier feedback circuit, only the 8 Ω output is made available at the rear panel
terminals.
– Find the secondary leads from the right channel output transformer (T1). Trim the leads to
be about 3-inches beyond the expandable sleeving (approximately 8 inches total from the
Inside chassis view
Potentiometer
Term 1
(low side)
Term 2
(arm)
Term 3
(high side)
Figure 5.13 Terminal numbering for chassis-mounted potentiometers.