This is a simple circuit which checks the polarity of the component. If you connected in right polarity the LED in the circuit will glow and it will not glow when you connected in wrong way. This is a ...

For years, telephone technicians have confidently approached phone-system troubleshooting with their trusty analog test sets. Also known as buttinsky or butt sets because they allow a repair person to ...

Scientific American is part of Springer Nature, which owns or has commercial relations with thousands of scientific publications (many of them can be found at www ...