Found in a 1967 American electronics magazine, this circuit has an input impedance of 2000 ohms. The circuit can be built with modern equivalent transistors.
Suggested by Philips documentation from 1968, this circuit uses components from the era that can...
This circuit uses NO sensors and was found in an American publication in the 90s. The supply must...
Found in American documentation from the 1990s, this circuit generates signals in the 350 to 500...