This circuit was found in an American documentation from the 90's. The transistor is a general purpose one. The circuit oscillates well between 12 and 30 MHz with the indicated components.
With the circuit shown, you can have a fast response with a Darlington configuration. The circuit is...
We found this multiple thermostat circuit in July 1980 Radio Electronics magazine. It uses...
Mouser Electronics is already providing new MOSFETs EF SIHx28N60EF of Vishay series for voltages...