ground loop hum from cable tv

drphoto · « **on:** 6 Dec 2003, 07:14 pm »

I tried to run sound from my tv to my 2 ch audio. I get a nasty ground loop hum from the TV cable. How can I get around this? Drive a new ground stake and attach the cable ground wire to it?

Tonto Yoder · « **Reply #1 on:** 6 Dec 2003, 07:35 pm »

http://www.dplay.com/tutorial/cablehum.html

drphoto · « **Reply #2 on:** 6 Dec 2003, 07:59 pm »

Thanks Tonto. That's an easy fix, and there was a lot of other good info linked from that site.

Tonto Yoder · « **Reply #3 on:** 6 Dec 2003, 09:12 pm »

There are also the mystery black boxes---Mondial M.A.G.I.C & something by Tributaries--designed to address cable hum, but they're in the $100 ballpark. I'm unsure if they have some extra circuitry that makes them more effective or if they're the same transformers in a pretty box????

I'd be inclined to try the Radio Shack/DIY route first.

Mad DOg · « **Reply #4 on:** 6 Dec 2003, 09:26 pm »

Quote from: Tonto Yoder

I'd be inclined to try the Radio Shack/DIY route first.

the rat shack DIY solution does the trick for cheap...

Tonto Yoder · « **Reply #5 on:** 6 Dec 2003, 09:35 pm »

Cheap?? Cheap???
Any real audiophile is gonna replace those F connectors with BNC's, the wire with some Cardas, put the transformers on some isolation platform,
shield with ERS and damp vibrations with some Josephson barbell-mass loading.

Espo · « **Reply #6 on:** 6 Dec 2003, 11:28 pm »

Does this fix limit the bandwidth for digital cable TV? I thought the Jensen VRD-1FF for about 50 bucks was a good solution since the bandwidth goes up to 1300 mhz?

wreilly · « **Reply #7 on:** 7 Dec 2003, 11:53 am »

I have the Mondial Magic, it's pricy but itt's the best one Iv seen. Works great on Digital Cable.

HifiDan · « **Reply #8 on:** 7 Feb 2004, 07:17 pm »

I had the same problem. I got an isolator ground cable transfo. It is about 1 inch in dia and about 3 inches long,and it's made of aluminium. I guess there are 2 coils and the ground is lifted. There is no name on it thou. Works very well and it's only 14.95 CDN.
I got mine at an audio shop doing bar and disco installation. Apparently they use this a lot with Sat dish, etc.
Kill the hum ...

Hifidan
The 75/300 Ohms thing doesn't work with digital t.v and you loose at least 10 db of signal going this route.

vpolineni · « **Reply #9 on:** 17 Mar 2004, 05:57 am »

I just noticed that I have the same problem...would this work?
http://www.audiocircle.com/index.php?topic=7417&highlight=hum

Rob Babcock · « **Reply #10 on:** 17 Mar 2004, 07:34 am »

Yep. I bought one from him and it works like a charm. The ground loop caused by my cable was bad enough that I disconnected it when I wasn't watching TV. But that little thing fixed it right up!