WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
Building, troubleshooting and testing of these amplifiers should only be
performed by someone who is thoroughly familiar with
the safety precautions around high voltages.
I've routinely used the LM317 as a CCS. Works great. But it's only good down to 10mA. Does anyone know of a similar 3-terminal regulator that works down to 1mA?
