We found this circuit in a 1977 National Semiconductor Databook. The circuit can use other FETs like the BF245 and has an input impedance of 10 megohms. The circuit gain is unitary.
This circuit uses three inverters to generate a rectangular signal whose frequency depends on R1...
This simple multivibrator circuit generates a 1 kHz signal rich in harmonics. The circuit is from...
The figure shows how to change the frequency of a 5 V LED blinking. The capacitor can have other...