You’ve probably seen probes that detect live wires in, for example ... voltage on a switch that is turned off or a Christmas tree light that is burned out. There are several different circuits ...

Kelvin probes are a special type of probe for making accurate resistance measurements using four wires and, in fact, the probe’s jaws are electrically isolated from each other. We liked [Tom’s ...

In the sensing optical fiber, probe light within the Brillouin scattering bandwidth co-propagates with a pilot light that has the same optical phase as the probe light at the input of the sensing ...

In this article, we'll show you how to replace the bulb, and if that fails, we'll show you how to diagnose a bad socket and probe the wiring with a simple 12-volt automotive test light.