Found in an English publication from the 1980s, this circuit can be built with equivalent transistors such as the BC549. The signal must be applied to an external amplifier.
This circuit is from a Linear Technology integrated circuit manual from the 1990s. The circuit...
The IC used in this project is not common these days, but if you have one you can build a high...
With this circuit, it is possible to excite a white LED or another type of high brightness with...