Found in documentation from the 1990s, it uses a sound effects integrated circuit, the SN7677 from Texas Instruments. Unusual component these days.
The presented circuit uses a symmetrical power source to supply an amplifier with the LM139 or...
This circuit was obtained from the 1995 Encyclopedia of Electronic Circuits Volume 5. The circuit...
The circuit shown is from the 1994 Linear Applications Handbook by National Semiconductor. Some of...