What is a ground loop?
Contemporary electrical codes in the US and Canada require that all wires entering a structure (electric, telephone, cable, satellite, etc.) be common grounded to the same electrode. A ground loop occurs when any piece of equipment or any incoming wire is connected to a different ground or grounds.
An AC current that can be produced in a cable. This is usually caused by parts of the system being fed from different electrical sources resulting in different earth potentials at each end. The result is interference on the signal, usually in the form of dark bands across the monitor and on occasion tearing in the top third of the image.
