This circuit was found in an Electronics World of 1968. The transistor can be any general purpose and the double T must be set to R3 for the desired effect.
This two-transistor circuit was found in the January 1994 issue of Electronics Now. The circuit can...
This simple circuit can be used to power a simple communication system using ordinary telephones....
This circuit to increase the sensitivity of instruments to 100 uA (or close to it) was found in...