Found in Popular Electronics from the 90s, this circuit generates signals in a frequency range set to R7 and basically determined by C1. Operational and equivalent transistors can be used.
This circuit was found in a Modern Transistor Workbook from 1965. The circuit sends signals from a...
Unlike the previous circuit, this circuit from Electronics Now, October 1993, has the load...
This circuit can detect static charges or extremely low voltages. The circuit was found in ancient...