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RE: TubeCad Error re: LTP?

Posted by cpotl on June 11, 2021 at 05:11:07:
"I fail to see the error. The closer the CCS is to ideal the closer the two plate resistors would need to be in value and in theory a perfect CCS with identical tubes would result in the need for matched resistors."
The error is that John Broskie is saying the two resistors should *not* be the same; he says that the left-hand one should be smaller.
By the way, I think the resistors should still be of equal value even if the two tubes are not matched? As long as there is no grid current, the current through the CCS must end up going through the two plate resistors, and when one plate current goes down the other must go up by an equal amount. This is true whether the tubes are matched or not.
This assumes there is no load on the outputs. If the outputs are loaded, things could get a bit more complicated. I wonder if that might be what he is driving at.