WhitakerAudio J C Whitaker 20 W Stereo Audio Amplifier, Руководство пользователя

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– Install the 0.1 A fuse (F301). Install in the socket for F301.
– Install the 6.3 A fuse (F302). Install in the socket for F302.
– Install the filament transformer T301 – Transformer, 115 V ac primary, 6.3 V ac
secondary . Carefully guide the component into place and solder. Note that pin #1 of the
device goes in the square pad.
– Install connector Conn301. Note that the locking lip should line up with the heavy line on
the PWB legend. Solder in place.
Clean the soldering iron tip.
– Mount the seven 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 in the upper left portion of
the board, use a #4 ground lug in place of the lockwasher. Tighten.
– Find relay RYL301, DPDT, 10 A, 24 V dc. Install in the RYL301 socket.
– Find the auxiliary power connector hardware. Set this package aside; it will be used later
to build the preamplifier power supply cable (if used).
If desired, a single light coat of acrylic conformal coating (MG Chemicals #419C-340G) may
be applied to the foil side of the board. In addition, brush-applied acrylic conformal coating (MG
Chemicals #419C-55ML) may be applied the B+ terminal on the preamplifier power supply
PWB. Using the brush provided, apply a light coat at the base of the quick-disconnect terminal
post so that it covers the immediate vicinity of the PWB pad.
Assembly of the preamplifier power supply 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 power supply board aside; it will be used later.