Super cool circuit!You can linearize this by putting another 1M from Gate to Drain as feedback. It reduces distortion quite a bit if I recall correctly. I feel like I may have added a DC blocking cap also between the added resistor and the drain but I'm a little fuzzy on this - It was 20 years ago.
VDR says that voltage will divide proportionally to resistance in a series loop. Thus, if you know one resistance and the ratio of the voltages, you can find the other resistance (e.g., if it has one-tenth the voltage, it must have one-tenth the resistance.
If you were running this circuit from a 9v source, like a guitar pedal, would you need something like a charge pump to provide a negative voltage for the voltage control of the jfet?
OK, so it’s a variable resistor. Why is it being used in parallel to the load? I’m assuming to maintain biasing in linear region. Can it be employed in series with the load? In parallel and in series to other jfet (resistors)?
Love it! Thank you!
Super cool circuit!You can linearize this by putting another 1M from Gate to Drain as feedback. It reduces distortion quite a bit if I recall correctly. I feel like I may have added a DC blocking cap also between the added resistor and the drain but I'm a little fuzzy on this - It was 20 years ago.
Yep. You need the cap otherwise the added resistor will spoil the bias and the control won't be the same.
Can you explain how you're using the voltage divider rule to calculate that Rd value?
VDR says that voltage will divide proportionally to resistance in a series loop. Thus, if you know one resistance and the ratio of the voltages, you can find the other resistance (e.g., if it has one-tenth the voltage, it must have one-tenth the resistance.
@@ElectronicswithProfessorFiore got it, thank you!
If you were running this circuit from a 9v source, like a guitar pedal, would you need something like a charge pump to provide a negative voltage for the voltage control of the jfet?
You might consider using a P channel FET.
OK, so it’s a variable resistor. Why is it being used in parallel to the load? I’m assuming to maintain biasing in linear region. Can it be employed in series with the load? In parallel and in series to other jfet (resistors)?
Yes and yes. You'll want to stay tuned for an upcoming video covering an analog switch using JFETs.
Often used in audio compressor circuits
Thank you.