Written in an article in Radio Electronics magazine in April 1987, this circuit triggers an alarm via a relay. Details of the sensor are given in the article.
This simple preamplifier was published in Radio Electronics magazine in February 1958. The battery...
The sensors in this circuit are NTCs and PTCs that work in a differential way by directly...
This interesting op-amp signal generator circuit was found in a 1977 documentation. The circuit has...