04-03-12: Chadnliz
You dont need any added filter if you have a correct earth ground, your provider can fix a faulty ground for free.
I agree proper grounding is important. And I would urge everyone with CATV to make sure the CATV cable grounding block is grounded properly.
The CATV cable grounding block per NEC shall tie, connect, to the main grounding system of the electrical service. Problem is NEC allows CATV companies many options where they can make the connection in my opinion. And NEC could care less about ground loop hum on an audio systems.
In this case NEC concern is lightning protection.
So the block could be grounded per NEC code and a difference of potential could still exist between the shield of the CATV RG6 coax cable and the branch circuit safety equipment grounding conductor.
If calling the CATV provider fixes the ground loop problem great.... If it does not install the ground loop isolator.
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