WhitakerAudio 60 W Stereo Power Amplifier, User And Assembly Manual

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60 W Stereo Power Amplifier
3) Properly orient the socket with respect to the PWB and insert the wires into their
respective pads.
4) After all wires have been correctly inserted, mount the socket on to the standoffs using
the #4 screws provided.
5) Solder the wires to the pins from the component side of the board. Trim the excess
length.
The final step in assembly of the right channel PWB is to make the heater connections to the
three sockets on the PWB. The following procedure is recommended.
– Identify pins 4 and 5 on the 9-pin tube sockets and pins 2 and 7 on the 8-pin tube sockets.
These pins are used for the heater connections.
– Unscrew and remove the standoff adjacent to pins 4 and 5 on the V1 socket. This will
facilitate access to the pins.
– Open the “Heater Circuit Wire” package and cut two 6-inch pieces of #22 green heater
wire.
– Place one piece of 1/2-inch long heat-shrink tubing over one end of each wire.
– Crimp one wire on pin 4 of V1. Solder in place. When soldering, make sure the heat-
shrink tubing is pushed back on the wire so it is not near the soldering point. If the heat-
shrink tubing gets hot it will be very difficult to slide into position later.
– Crimp the other wire on pin 5 of V1. Solder in place, keeping in mind the caution about
the heat-shrink tubing.
– Slide the heat-shrink tubing into position at the base of the socket. Apply a stream of hot
air to shrink the tubing over the pins. Be careful to not apply too much heat.
– Replace the standoff removed from the V1 socket. The screws should be finger-tight.
Remember to include the lockwasher on the component side of the board. The heater leads
should straddle the standoff.
– Twist the wires together and route to socket V3 (see Figure 5.2 d for placement). The wires
should be placed at socket-level. In this way they will be resting against the chassis when