Grid testers operate at high-frequency but are able to cover low-frequency ranges as well. There are two types of grid testers - scalar and vector. The first type quantifies amplitude parameters of the grid, while the second type is able to quantify phase properties as well. These gadgets usually comprise a signal creation device, a test set, and a receiving device. The signal source creates and sends a signal down the system while the test set directs it to a device you wish to test or a part of the grid that requires analyzing. The receiver measures the monitored parameters and sends them to a processor to be transformed into information and displayed on the screen.
There is also another network type that is commonly used in modern information transfer systems. Optical fiber cables are superior to regular electrical wires for a number of reasons and are used for information transportation in the Internet grids, television networks, etc. They operate with a different type of signal and need a different type of network analyzers. Though the working principle remains the same, a light source with an adjustable wavelength is used as a signal generator.