This sensitive touch key appears on this website from other sources. This version was taken from a 90s American documentation. The source must not be of transformerless type.
This circuit accelerates the tripping of a relay when energized. The circuit uses the CA3018...
The circuit shown is from the National Semiconductor 1994 Linear Applications Handbook. The base...
This ultra-simple circuit has the frequency determined by the LC network. Any general purpose JFET...