LTP and H3 distortion

[dgta]

If you can find a thermionic diode, or diode wired triode, that has the same Ri at the operating tail current, it can replace the tail R for wide range 3rd harmonic cancellation. (think of the Akido design, where a non-linear load and matching non-linear drive tube give linear results)

Not sure such a diode exists. Typical LPT tail current is a few mA to a few tens of mA. And the tail voltage is in the tens of volts or more. Is there a diode that drops let's say 80V at 20mA forward current?

Low power triodes may work in theory but you'd be exceeding both Vgk and Ig, no?

Good idea for further thought though.

 

[Hearinspace]

There are a LOT of diodes out there . . . . . . . multi amps at low voltage and single digit milliamps at multi K voltages.

When I built the mentioned circuit 15 years ago I knew that it would be in damper diode territory but still had to go through quite a few data sheets to find one that suited.


A quick look found this one, not far off your stated mark.