Hi baudouin0,
Like I said, I do have the circuit working and its accuracy is spot on, even at maximum power output. And it is not as complicated as you think when the right parts are chosen and applied correctly.
And again, measuring the cathode current will produce incorrect results because at the cathode you have the sum of the plate and screen currents.
Like I said, I do have the circuit working and its accuracy is spot on, even at maximum power output. And it is not as complicated as you think when the right parts are chosen and applied correctly.
And again, measuring the cathode current will produce incorrect results because at the cathode you have the sum of the plate and screen currents.
Nop I can see the high side measurement could be a current mirror. If your measuring to set bias then the ratio of plate to screen current is pretty constant with different spreads of the same type of valve and screen current is only a fraction of the plate current. I would imagine measuring cathode current and scaling would give you no more than a 5% error. In any case some of the screen current is going through your OPT so your using a bit of both. Nothing wrong with what you are doing in my books just not what I would do.
If your using the plate current in the micro as some sort of distortion cancellation - very interesting.
If your using the plate current in the micro as some sort of distortion cancellation - very interesting.
Beware that any hangin´on circuits attached to the anode wiring with their large voltage swings could provoke circuit instability due to increased area/ capacitive coupling to layout/sensitive input signals. The general rule is to keep high voltage signal carrying components short and direct.
I dread to think of any micro connected to 500V anode swings would think of being asked to measure, when for example my yellow Fluke 75 DVM immediately goes digit crazy on the slightest frequency. To get any type of consistent measurement one has to connect common-mode ferrites, all adding to parasitic complexity.
BB
I dread to think of any micro connected to 500V anode swings would think of being asked to measure, when for example my yellow Fluke 75 DVM immediately goes digit crazy on the slightest frequency. To get any type of consistent measurement one has to connect common-mode ferrites, all adding to parasitic complexity.
BB