I was told that the hum I get from my speakers sometimes is probably ground loop distortion. I understand that it means when your ground is coming from two different sources and they conflict. Is that about right?
Wayne Parham Messages: 18787 Registered: January 2001
Illuminati (33rd Degree)
Yes, that's right. Connect all equipment to the same wall socket. Also, if you have cable TV, install an isolator. It can be as simple as connecting a 75Ω-to-300Ω adapter followed immediately by a 300Ω-to-75Ω adapter. This will isolate the cable ground using a pair of antenna line matching transformers.
gofar99 Messages: 1949 Registered: May 2010 Location: Southern Arizona
Illuminati (5th Degree)
Hi to follow on with what Wayne said...I had a serious hum and noise problem when I attached the CATV cable to an FW tuner I was using. When I measured it the open circuit (measured with a high impedance meter) voltage was just over 30VAC. The current was small, but it really upset the ground. I ended up switching to an antenna.
I've always known that a ground loop results when pieces of equipment are plugged into the AC at different locations, then connected together by signal cables that have a shielding connected to the ground. I think both Wayne and gofar have offered great solutions.
This helps bunches guys. I knew that the occasional hum I get when I run a couple of my components had something to do with the ground. Now I can attack this problem and get it fixed once and for all. Thanks.