WhitakerAudio 60 W Stereo Power Amplifier, User And Assembly Manual, Page: 34 / 154

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– Repeat the connection process for each PWB-to-socket connection, being careful to match
up the right pad on the board with the right connection on the socket. (See Figure 5.2 c .)
This is best done by starting at pin 1 on one side of the socket, and on pin 9 on the other
side.
Note: The lead lengths for the octal tube sockets vary from one vendor to another. The
procedure described above works well for sockets that, when mounted, allow at least 1/4-inch
clearance above the board. Some socket leads, on the other hand, extend almost to the PWB pads.
In this case, it is recommended that the following procedure be followed:
1) Cut 6 pieces of 2-inch long bare #22 wire. Attach a wire to each of the active pins on
the octal socket (all except for pins 2 and 7, the heater terminals) and solder.
2) Cut the wires in descending length from pin #1 to pin #8.
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.
Table 5.1 PWB to Tube Socket Connections
Socket No. V1, 6U8A V2, 7027A V3, 7027A
Pin 1 yes yes yes
Pin 2 yes no, heater no, heater
Pin 3 yes yes yes
Pin 4 no, heater yes yes
Pin 5 no, heater yes yes
Pin 6 yes yes yes
Pin 7 yes no, heater no, heater
Pin 8 yes yes yes
Pin 9 yes