This simple circuit, found in American documentation, uses only one relay that locks when any of the sensors is activated. To reset, simply turn off the power for a moment.
This circuit is an excellent application for the PIC in audio, but the reader who intends to do...
To a 16-0hm load, this amplifier provides a power of 10 W. We found this circuit in a Motorola...
This reader with TTL logic compatible output uses an LM139 comparator. The circuit was found in...