WhitakerAudio JC Whitaker 20 W Stereo Integrated Audio Amplifier, Manual

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WhitakerAudio
– Mount R57 – 5 k
Ω
potentiometer – Bias Adjust Control. Note the tab extending from the
component toward the front of the device. Using a pair of long-nose pliers, bend the tab
down to the base of the potentiometer. Place a large flat washer on the shaft and add a
lockwasher. Insert the device through the mounting hole. Secure with a small flat washer
and nut. Before tightening the nut, orient the terminals so they are easily accessible from
underneath the chassis; the terminals should point away from the preamplifier PWB. Be
careful to not scratch the top-side finish when tightening the nut. Once the device has been
mounted, place the potentiometer in the approximate center position using a common-
blade screwdriver. The smaller-diameter nut provided with the control is used to secure
the position of the device to prevent accidental movement. Place the locking nut on the
shaft (finger-tight).
– Carefully peal off the backing for the top chassis decal. Position it on top of the chassis,
behind tubes V5 and V6. Apply the decal.
5.5.7 Wire the Transformer Leads
Find the female “quick-disconnect” connectors. In the following steps, the transformer leads will
be connected to their respective terminals on the circuit boards using these connectors. The lead
lengths from the various transformers may need to be trimmed to remove excess length. Make
sure to keep sufficient lead length to permit organized cable routing.
5.5.7.1 Cable Organization
To facilitate cable organization, it is advisable to install expandable flexible cable sleeving on
some of the transformer leads. A supply of this material is provided. To properly perform the
following steps, it will be necessary to have a heat gun on hand. (A common hair dryer may be
sufficient.) In addition, the preferred method of cutting the tubing is to use a so-called “heat
knife.” If such a tool is unavailable, scissors may be used. Note that two sizes of sleeving are
provided—a small size and a large size. Note also that two sizes of heat-shrink tubing are
provided—one small and one large.
– Cut two 6-inch pieces of small expandable sleeving. Cut four pieces of small heat-shrink
tubing, each about 3/4-inch long.