This circuit uses a PLL4046 oscillator to excite a piezoelectric ceramic. The circuit is from an October 1994 Electronics Now magazine.
This circuit was found in a 1980s documentation. The low voltage circuit uses a PUT. Transistors can...
June 2017 - Mouser Electronics has a broad line of Cree products for use in horticulture, such as...
The TDA2040 is not a common IC these days, but if you find one you can build this high quality...