This 100 kHz oscillator was found in a 1966 Motorola publication. The transistors are of types suitable for the generated frequency and L1 / C1 depend on that frequency.
This efficient filter against EMI has several coils, being L1 and L2 formed by 100 turns of wire...
This optical sensor circuit for a robot was found in the March 1986 issue of Radio Electronics magazine....
This circuit can provide both positive and negative voltage outputs from 2 to 12 V with current up to...