This circuit is from a 1966 publication. The frequency depends on the capacitors and on R1 which can have values between 47k and 2.2 M typically. The supply voltage can be between 200 and 300 V.
This circuit was suggested by Radio Electronics magazine in September 1983 in the new ideas...
We found this amplifier with high input impedance and low capacitance, using FET, in a...
This powerful pushbutton uses a power MOSFET. We found it in a Popular Electronics magazine from...