Found in an American 1980s documentation, this circuit compares signals from two TTL sources, providing an output that depends on the frequency difference. The circuit can be used as a shield.
January 2017 - The new Honeywell RSC TruStability ™ pressure sensor mounting board is available from...
The IC used in this project is not common these days, but if you have one you can build a high...
June 2016 - It can be obtained from Mouser Electronics the new gate driver optocoupler from...