Yes, yet another home made valve tester.
Not too sure how useful this will be for testing valves but it is occupying time whilst building.
Fitted two meters today, some 4 mm sockets and a few switches.
Red ones on left hand side for heater/filament.
Black same side for Grid.
To the right side two reds for anode and g2 and two blacks for Cathode & g3.
There is not enough space in the chassis for a power supply so I am going to fit the buck style PSU's into a metal box to provide a bit more heat-sinking and a couple of pots to set HT and heater volts, I have yet to sort a linear pot to set a negative Grid bias.
There is no plan to this, I never seem to make any as it is always down to what I can find in my bits and bobs boxes or what I can fabricate as I go along.
One HT output has the 4 or 40mA meter in series so by changing leads I should be able to either check g2 or anode current. Changing grid bias +/- 0.5Volt from spec, I hope should allow me to figure gm.
I am sure there are other things I can do with it, but it is a start. Got to make up the jumper leads as well.
Adrian
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