WhitakerAudio JC Whitaker 20 W Stereo Integrated Audio Amplifier, Manual

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20 W Stereo Integrated Audio Amplifier
– Install C18, C55, C57, C60, C62 – 0.01 µF disc, 1 kV . Solder in place.
– Install C56 – 82 µF, 500 V . electrolytic. Bend the pins to provide a good mechanical and
electrical connection. Solder in place. Be certain to observe proper polarity.
– Install C58, C59 – 10 µF, 100 V . electrolytic. Solder in place. Be certain to observe proper
polarity.
– Install C61 – 100 µF, 100 V . electrolytic. Solder in place. Be certain to observe proper
polarity.
– Install C63, C64 – 1000 µF, 25 V . electrolytic. Solder in place. Be certain to observe
proper polarity.
Clean the soldering iron tip.
– Install D52 – rectifier, 2 A, 1 kV . Solder in place, providing about 1/4-inch clearance
above the board. Be certain to observe proper polarity. Note that the banded end of the
diode connects to the square pad on the PWB
– Install D53 – zener, 60 V, 5 W . Solder in place, providing about 1/4-inch clearance above
the board. Be certain to observe proper polarity.
– Install D54 – zener, 56 V, 5 W . Solder in place, providing about 1/4-inch clearance above
the board. Be certain to observe proper polarity.
– Install CR51 – bridge rectifier, 100 V, 2 A . Solder in place, providing about 1/2-inch
clearance above the board. Be certain to observe proper polarity. The positive terminal
goes to the square pad.
– Install VR52 – thermistor, 20
Ω
cold . Solder in place.
– Find VR3 – varistor, 18 V dc . Set this component aside; it will be installed later.
– Install the four-terminal Molex barrier strip TB4 . Solder in place.
– Mount the two 4 terminal Molex contact headers at the Conn3 and Conn4 positions.
Solder in place. It may be necessary to hold the header in place from the component side
of the board until the first terminal is soldered.