This circuit was found in ancient American documentation. It makes use of the operational amplifiers of the time, but it can be implemented with modern equivalents.
The illustrated circuit uses the AUIRS2301 S from International Recfifier (www.irf.com) and is...
This timer was found in English documentation from the 80's. The integrated circuit is common...
This circuit is from an Electronic Design of the 90's. The circuit can be implemented with more...