This circuit was found in a Popular Electronics from the 90s. The power source must be symmetrical and the operational amplifiers can be 741.
This is one of the many anti-deboucer circuits the reader can find on this site. The base is TTL...
The idea of wearables is not new and does not necessarily need to be implemented with...
General Electric suggests this circuit in a 1980s documentation. The operational of the time is...