WhitakerAudio J C Whitaker 20 W Stereo Audio Amplifier, Manual

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20 W Stereo Audio Amplifier
5.1 Assembly of the 20 W Stereo Amplifier PWB #1 (Right Channel)
Check the shipping box for the major component groups. Find the 20 W Stereo Amplifier PWB
#1 (Right Channel) 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
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.
Note that this section describes assembly of two circuit boards:
• Amplifier PWB #1 (right channel)
• Rectifier PWB
Unless otherwise stated, the following steps apply to the amplifier PWB. The estimated time
required to complete assembly of the two boards is three hours.
After reviewing the Construction Techniques section of this manual, begin populating the
circuit boards. 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 amplifier board.
There are 31 positions in all. Solder in place.
– Install the quick-disconnect male tabs using the pads provided on the rectifier board.
There are 15 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.
The proper procedure is illustrated in Figure 5.1.
Clean the soldering iron tip before moving on to the following steps.
– Install R1 – 1 m
Ω
, 0.5 W . Solder in place.