The operational amplifier and the sensor used in this National Semiconductor circuit are not common today, but the configuration can be adapted to use current components.
We found this relaxation oscillator in a 1967 General Electric documentation. The frequency is given...
This circuit generates a 20 MHz sinusoidal signal from a 10 MHz crystal. It is found in the 1992...
This circuit is from a 1967 publication. The potentiometer above 4M7 is the critical component. The...