WhitakerAudio JC Whitaker 20 W Stereo Integrated Audio Amplifier, Manual

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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.
– Find the 0.5 A fuse (F101). Install in the socket.
Examine the main preamplifier PWB, in particular the mounting holes at the bottom of the
phono preamplifier section of the board. There are two mounting holes. These holes support not
only the board against the chassis, but also the aluminum shield and the daughter board PWB.
– Using two male/female (M-F) 3/4-inch #4 standoffs and two female/female (F-F) 3/8-inch
#4 standoffs, mount the daughter board over the phono preamplifier section of the PWB.
The order of the hardware is as follows: 1/4-inch #4 screw / lockwasher / daughter board /
M-F standoff / lockwasher / PWB / F-F standoff. Tighten.
– Mount the remaining five standoffs on the foil side of the board using 4-40 hardware
provided. Use a lockwasher on the screw head (component side) of the board. Standoffs
are positioned at the four corners and lower center of the PWB. For the standoff on the
upper portion of the phono preamplifier are of the board, use a #4 ground lug in place of
the lockwasher. Tighten.
If desired, a single light coat of acrylic conformal coating (MG Chemicals #419C-340G) may
be applied to the foil side of the preamplifier PWB.
Assembly of the preamplifier PWB has now been completed. Check the board for proper
installation of all components. Look for bad solder connections or solder splash that might cause a
short-circuit.The finished board are shown in Figure 5.5.
Set the preamplifier board aside; it will be used later.