boost circuit

Here is the boost circuit board layout, and also the wiring for selecting 12AX7 or 6N2P preamp tubes:



There are two 12AX7 sockets in the preamp chassis so far: preamp and phase inverter.  The third socket for the boost will be drilled in midway between the two existing sockets.
The boost circuit will be laid out on a small PCB board, in strip fashion like the other two existing boards.
Also, a hole will be drilled to one side of the three sockets, for the tube type selector switch (12AX7/6N2P).



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