This circuit is from NASA documentation from the 1980s. The circuit shows how to obtain a stable optical coupler system. The circuit can be used as a shield.
This circuit is from an 80's Radio Electronics. The circuit has several output options for 50 mA...
The absence of a pulse in the pulse train applied to the input of this circuit causes a high level...
This is one of the many anti-deboucer circuits the reader can find on this site. The base is TTL...