Serious hum problem. Help

Bd -- forgive me, I failed to mention the cheap fix (i.e. any kind of 75 ohm isolation transformer, homemade or commercial) doesn't pass digital cable signals.

I knew that, just forgot to say so. I don't know how the new isolator units work or if they can even be duplicated by DIY.

Bdgregory,

Thanks for the "heads up" on the MCM Ground Loop Isolator.
Had the same problem with the coax cable causing the hum (and I also have Comcast as my digital cable), that you were having, and was considering getting the Mondial MAGIC Box ($99) but MCM Ground Loop Isolator solved the problem for much less money.

Once again, thanks.

i had the same problem and eliminated it at no extra cost to me. i used the power conditioner's (power strip's) coaxial "in" and "out" between the wall and the cable box. i suppose you need this coaxial feature on your strip or conditioner, but it works for little or no money. maybe it is grounded separately. dunno.

revision on that last comment. i too have comcast digital cable and there is a problem transfering information when using the power conditioner's coax in and out. back to the drawing board. the mcm product looks like the best option.

Fickle75, I understand from some other members' posts that if you have HD cable, that most of the cable ground isolators won't pass the HD signal ;--(( Bummer!

As for the "coaxial "in" and "out" between the wall and the cable box" it depends on the particular power conditioner unit. In most of them, the "coaxial in and out" just runs the cable signal thru a filter, but it doesn't really isolate the ground, so hum is still created due to the ground loop thru the cable system.
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