WhitakerAudio J C Whitaker 20 W Stereo Audio Amplifier, Manual

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20 W Stereo Audio Amplifier
extend one or more of the leads, do not trim the wires from the transformers until they are to be
connected to the PWBs.
– Locate the chassis grommets. There are 5 for the 1/2-inch holes and 2 for the 3/4-inch
holes. Install the grommets.
– Examine the transformers (T1, T2, T51, and L51). A nameplate sticker can be found on
the bottom of each device. Carefully peal off the sticker and apply it to the under-side of
the chassis in the approximate location of the transformer. This will serve as a reference
for connections, and service at a later point if needed.
– Locate the power transformer, T51. Examine the mounting holes. Note that two additional
holes are provided within the confines of the base of the transformer. These holes are used
for the support standoffs for the power management PWB. Install 2.5-inch standoffs using
countersunk 3/8-inch long #6 screws. Include a lockwasher between the chassis and the
standoff. Tighten.
For transformer installation, the sequence of #6 mounting hardware is as follows (from top to
bottom): screw / flat washer / external tooth lockwasher / transformer mounting tab / chassis / nut
with captive lockwasher. For the mounting position that includes the ground lug, insert the lug
between the mounting tab and the chassis.
– Install power transformer T51 using the #6 hardware provided. Carefully guide the leads
through the holes in the chassis. Be sure to include the grounding lug wire. Route the
grounding wire through the chassis along with the transformer leads. The primary winding
leads (white, brown, blue, black, etc.) should face to the rear of the chassis.
– Install right channel output transformer T1 using the #6 hardware provided. Carefully
guide the leads through the holes in the chassis. Be sure to include the grounding lug wire.
Route the grounding wire through the chassis along with the transformer secondary leads.
The speaker leads (yellow, green, white, black) should face to the rear of the chassis.
– Install left channel output transformer T2 using the #6 hardware provided. Carefully guide
the leads through the holes in the chassis. Be sure to include the grounding lug wire. Route
the grounding wire through the chassis along with the transformer secondary leads. The
speaker leads (yellow, green, white, black) should face to the rear of the chassis.