WhitakerAudio 60 W Stereo Power Amplifier, Руководство пользователя и по сборке, Страница: 49 / 154

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60 W Stereo Power Amplifier
– Mount the six standoffs on the foil side of the board using 4-40 hardware provided. Use a
lock-washer on the screw head (component side) of the board. Standoffs are positioned at
the four corners of the PWB and on each side of the tube socket. Note that one standoff set
includes a ground lug; mount on the corner of the PWB adjacent to VR51. The ground lug
goes on the component side of the board. The screws should be finger-tight for now.
– Mount the octal tube sockets on the appropriate standoffs. Note the key on the socket. The
key faces the side of the board with the barrier strip. To facilitate installation, bend the
unused pins (1, 3, 5, and 7) at an angle to keep them out of the way. Place the socket in the
proper orientation over the PWB so it rests on the standoffs. The top of the socket (the side
the tube plugs into) should face outward. Loosely tighten the mounting screws. See Figure
5.2 a .
– Install connecting wires from the PWB pads to the tube socket pins. Solder in place.
Materials for these steps can be found in the “Tube Socket Hookup” package. Note that
the PWB contains pads only for the active pins used on the socket (pins 2, 4, 6, and 8). The
recommended procedure for installing the connecting wires is as follows:
1) Feed a bare wire from the component side through the pad and into the socket
soldering tab.
2) Crimp in place (see Figure 5.2 b ).
3) From the component side, pull the wire tight and solder in place
4) Trim the excess lead length.
5) Solder the socket tab.
– Check the PWB for proper installation of all components. Look for bad solder connections
or solder splash that might cause a short-circuit.
– Find the package of quick-disconnect connectors. Set them aside; they will be used later.
Assembly of the power supply PWB has now been completed. (Figure 5.4) Set the board
aside; it will be used later.