Found in a 90’s Popular Electronics, this circuit uses two CMOS inverters to generate a signal of a few hundred hertz determined by C1 and the R3 setting.
The circuit shown in the figure is suggested by ON Semiconductor (www.onsemi.com), based on its...
September 2016 - can be found at Mouser Electronics the new amplifiers with digital variable gain...
This simple 1-transistor audio preamplifier appeared in the June 1968 Radio Electronics magazine. The...