[MrFixr55]

When you get around to converting to a diode detector, I think that you can get away with just changing the cap from 0.00025 to 0.01. The Grid leak resistor can likely remein the same. You can crank the voltage up to 67V and apply the 4.5VC- to the leg of the grid leak that does not connect to the grid (usually grounded, lift the ground and put 3 1.6V batteries in place.

I have been meaning to test the quality of sound from 01As used as a preamp. Haven't gotten around to it.