Hi, I learned about JFET current source and just built one on my bread board using J109. It's the simplest form with source and gate shorted together. According to my understanding of JFET behavior, when I change the drain resistor from 500 ohm to 300 ohm the current should not change but I got different result when I measured it. The current is 9V(my power supply) divided by the resistance. Is their anything wrong with my understanding?
Thanks very much !
Thanks very much !