We found this circuit in a 1980s General Electric documentation. It appears from other sources in this section. The circuit makes use of diacs and SCRs of the time.
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...