19-07-2016, 04:23 PM
I know the feeling Lawrence 
Splendid fellow young Jeffrey. Think of all those EL34/37s. If someone gave you one which needed a set of Valves you'd need a new Mortgage to afford it.
I wasn't thinking of a direct copy, just getting some idea of how they went about it.
I was thinking along the lines of generating a stabilised Negative Supply as a Reference to the Pot then comparing the Pot Slider to a sample of the Output. The result of that comparison would be the Control Voltage to the Series Pass Valves. I fear it will have to be SS.
Some Sums called for methinks.
Alan
Splendid fellow young Jeffrey. Think of all those EL34/37s. If someone gave you one which needed a set of Valves you'd need a new Mortgage to afford it.
I wasn't thinking of a direct copy, just getting some idea of how they went about it.
I was thinking along the lines of generating a stabilised Negative Supply as a Reference to the Pot then comparing the Pot Slider to a sample of the Output. The result of that comparison would be the Control Voltage to the Series Pass Valves. I fear it will have to be SS.
Some Sums called for methinks.
Alan
