This simple optical alarm circuit was found in the 1991 Electronics Experimenter Handbook. The circuit uses a lamp as the emitter but can use LEDs.
The presented circuit generates a pulse whose delay in relation to the input depends on RC. These...
Found in documentation from the 70s, this circuit makes use of SCRs of the time. Modern equivalent types...
This circuit was found in a Linear Technology manual from the 1990s. The circuit makes use of the...