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 found in the July 1969 issue of Radio Electronics magazine. It also appeared in...
This circuit can function as a high-power shield completely isolated from the power grid. We found...
This circuit has as a critical component the transformer that has low voltage windings for the...