Published in an old Popular Electronics, this circuit makes use of components that are still current. The circuit must be powered with 9 V and eventually adapted to function as a shield.
July 2017 - Microchip's new MCP39F511 demonstration and development boards, which consist of...
This circuit, which controls both the temperature and the level of a liquid in a reservoir, was...
This circuit provides a constant current of 1 mA, stabilized by an LED, which can be equivalent to that...