WhitakerAudio J C Whitaker 20 W Stereo Audio Amplifier, Manual

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WhitakerAudio
5.4 Assembly of the Power Management Module
Check the shipping box for the major component groups. Find the power management box. Set
the other boxes aside for now. Organize the components in a logical manner, grouping resistors
together, capacitors together, and so on. Note that a schematic diagram of the power management
system is provided, along with a copy of the PWB component layout. The component layout sheet
is a useful reference as many of the part numbers are obscured when the components are installed.
The estimated time required to complete assembly of the power management PWB is two hours.
After reviewing the Construction Techniques section of this manual, begin populating the
board. As the packing envelopes are used, set them aside for recycling. Before beginning, clean
the soldering iron tip.
– Install the “quick disconnect” male tabs using the pads provided on the board. There are
13 positions in all. Solder in place.
Note that the mounting pins fit tight into the board. This is normal. Use a pair of pliers to hold
the tab while inserting the pins into the PWB. Make sure the PWB is resting on a soft flat surface
while the tabs are installed. It is most efficient to install all of the tabs and then turn the board over
and solder in place. Be careful to not damage the board while installing the tabs. While not strictly
necessary, it is recommended that the flat side of the tab be oriented in the same direction for all
posts.
Clean the soldering iron tip before moving on to the following steps.
– Install R201 – 8.2 m
Ω
, 0.5 W . Solder in place.
Caution: leads may tend to fly toward the face when they are cut. Wear protective glasses. For
all steps that follow, excess lead length should be trimmed after the component is soldered in
place.
– Install R202– 15 m
Ω
, 0.5 W . Solder in place.
– Install R203, R206, R212 – 150
Ω
, 0.5 W . Solder in place.
– Install R204 – 430 k
Ω
, 0.5 W . Solder in place.
– Install R205 – 33
Ω
, 0.5 W . Solder in place.
– Install R207 – 1 k
Ω
, 2 W . Solder in place.