wiring the tube sockets

 

Red/white twisted pair is heater power: white to pins 4 + 5, and red to pin 9, for 6.3VAC operation.

Colour code for tube terminals:

black = anode (plate), green = grid, yellow = cathode.

This comports approximately with the "standard" colour code used in other vintage tube gear, such as Fender and Marshall -- except anode should be blue, not black.  Blue is not a colour available in 4-conductor phone wire, so...



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