Tech

Ground Loops Ground loops can happen even in the most carefully planned A/V system. When ground loops happen in a video system, the result is unwanted hum or video hum bars. In cable TV systems, the power supply for the cable system amplifiers is powered by a different source than the equipment that is used to enjoy the programming. The National Electrical Code requires the cable system to be bonded to the power service entrance ground, but in actual practice, this is not always the case. Even when the code is properly observed, there are other factors that can cause...