To add a Dwell control like on the
standalone reverb to a Fender amp
with reverb, remove the 1 meg resistor and replace it with a pot.
One end of the pot goes to ground and the other end
the capacitor - just like it is now.
But the wiper (middle lead) of the pot goes to the grid
2 and 7) of the tube.
The existing wire goes under the board and attaches to
existing 1 meg resistor and 500 pf cap.
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