This circuit appears on this site from different sources. This is from documentation from the 1980s. The operating system used is uncommon and can be replaced by a more modern equivalent.
The integrated circuits used in this 1999 project are not very common today. However, they can be...
This circuit is from a 1992 Electronics Handbook. The circuit generates a special tone effect for...
This circuit was found in a 90s documentation from National Semiconductor. The integrated circuit is from...