Found in a Popular Electronics from the 90's, this circuit can generate frequencies according to the values of the employed components, according to the table next to the diagram.
This circuit is used in transceivers, enabling input selection by diode switching through polarity...
This configuration was found in an American publication from the 90s. Operators admit equivalents just...
This circuit was found in an Italian magazine Elettronica Prática of 1977. The transistors can be...