Found in a 1990s US publication, this alarm circuit detects when a light beam is interrupted. Optical resources may be used for the sensor and instead of the alarm a relay may be used.
This circuit was obtained in a 1975 documentation. The maximum frequency depends on the diodes and the...
Found in a 1990 Hobbyst Handbook this circuit has an output power of a few tens of watts and...
The circuit shown is a constant current source which allows the reading of resistors on a very low...