WhitakerAudio 60 W Stereo Power Amplifier, User And Assembly Manual

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WhitakerAudio
diode connects to the square pad on the PWB. This same convention is used for all other
diodes on the PWB.
– Install D52 and D53 – zener diode, 200 V, 5 W . Solder in place, providing about 1/2-inch
clearance above the board. Be certain to observe proper polarity.
– Install D54 – rectifier, 2 A, 600 V . Solder in place, providing about 1/2-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. Note that the leads will need to be spread in order to properly mate
with the pads.
– Install VR51 – power thermistor, 5 Ω cold . Solder in place, providing about 1/2-inch
clearance above the board.
– Install VR52 – thermistor, 20 ΩW cold . Solder in place.
– Install the four-terminal Molex barrier strip. Solder in place.
– Find tube V51 and set it aside in a safe place. The tubes will be installed during the final
checkout process.
Examine the fuse holder. Some devices have a small plastic pin protruding from the mounting
side. This pin must be clipped off or the holder will not mount flat against the PWB.
– Install the F51 fuse holder using the hardware provided. Use short bare connecting wires
from the terminals to the pads on the PWB (use wire found in the Tube Socket Hookup
Wire package). Solder in place. Tighten the set screw (do not over-tighten).
A method that works well for the above step is to first mount the fuse block with the hardware
finger-tight. Then feed the bare wire up from the foil side of the board and affix it to the terminal.
Solder and then repeat for the other side of the component. Finally, tighten the mounting screw.
Note that fuse holder F52 is not used in this implementation.
– Find the 0.5 A fuse. Install in the F51 socket. Note that two fuses are provided. Save one
for future use if needed.