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Repair / Help Forum => Repair / Help => Topic started by: OldiesButGoodies on April 06, 2013, 12:56:02 PM

Title: Humma Humma - More thoughts on the battle against humm
Post by: OldiesButGoodies on April 06, 2013, 12:56:02 PM

I did a few tweaks to the system this morning and would like to share the results. 

Battle number 1 was against cable box hum due to differences in the cable TV ground vs my ground etc.  I first blocked this somewhat successfully by wiring two 75-300 transformers together.  That worked to a degree. Then I procured a specialized filter - the TII ground loop isolator:

http://www.amazon.com/TII-Ground-Loop-Isolator-220/dp/B0070Q6URO/ref=pd_sim_e_3 (http://www.amazon.com/TII-Ground-Loop-Isolator-220/dp/B0070Q6URO/ref=pd_sim_e_3)


(http://i1122.photobucket.com/albums/l538/namikis/IMG_0881_zpsbbc4ee3a.jpg)

(http://i1122.photobucket.com/albums/l538/namikis/IMG_0878_zps1f2070c4.jpg)

(http://i1122.photobucket.com/albums/l538/namikis/IMG_0874_zps312e45c1.jpg)

(http://i1122.photobucket.com/albums/l538/namikis/IMG_0882_zpsdeac78da.jpg)

The results were excellent.  The hum is now completely gone from my home theater.  This is a highly recommended tweak,  and cheap for $17.

The home theater side of my set up uses the Emp Tek 1010i subs,  so the Bobfather's True Sub is not involved.  That was my second challenge for the day - look for a separate post later today on that....

 8)

Title: Re: Humma Humma - More thoughts on the battle against humm
Post by: Anders on April 06, 2013, 02:33:22 PM

Cable TV grounds are never at the same potential as an actual house ground.

Title: Re: Humma Humma - More thoughts on the battle against humm
Post by: MacGeek on April 07, 2013, 07:36:54 AM

Hum sucks.  Glad you got rid of it.