This circuit visually indicates that a high voltage is present in an outlet or other point. The neon lamp is common, and the appearance of the assembly is suggested in the same figure.
The output power of this wireless intercom for the 27 MHz (11 meters) range is in the order of ½ W,...
In the figure we have the way to implement an Exclusive OR or XOR gate with CMOS or TTL...
This useful circuit is used to test the insulation of cables, appliances, leaks in high voltage...