This small low current inverter operates at 20 kHz frequency. We found it in documentation from the 1980s. The integrated circuit is from that time.
The sensor for this circuit, found in a 1992 publication, is a phototransistor. The power is...
This circuit can generate signals of frequencies up to 1 or 2 MHz, tuned in the capacitor. The...
Suggested by Philips documentation from 1968, this circuit uses components from the era that can...