This 9 V battery eliminator was found in Radio Electronics magazine from June 1966. The transistor is of medium power and must be equipped with a small heat sink.
This second-order low-pass Salen-Key filter was obtained from an American 1980s documentation. Formulas...
July 2017 - Mouser Electronics is providing the TE Connectivity PTF Series Platinum family RTD...
The basis of this circuit is an LM380 that drives a speaker that emits sound when moisture is...