Shielded transformer - DIY

[2Bak]

I want to shield a toroid in a Gainclone cabinet. The toroid will be very close to the LM3875T's.
Found these solutions with cobber:

http://www.passdiy.com/images/gallery/a5-p3-f2.jpg
http://www.passdiy.com/images/gallery/boz-p7-f5.jpg

Tell me some more on DIY transformer shielding...
Materials, do's and don'ts etc...

/Jan

 

[2Bak]

...I was lucky to find transformer copper band. Will try it and then post my results afterwards...

thanks

 

[Eric]

I, too, had some problems when I placed my supposedly shielded toroid transformer into my chassis. The magnetic fields it generated bled into my signal wires and induced a significant hum in my speakers. After removing the transformer from the chassis, the hum was gone.

So, I got some copper flashing from my local hardware store and cut a strip a little longer than the circumference of the toroid and about 1.5 times the height of the transformer. I left small tabs on the bottom so that I could attach it to the chassis and put the toroid and bridges in the center of it. Upon powering up my amp, it was now nice and quiet. The hum and buzzes are gone!

I think it cost me about $5 for 12" by 24" of copper flashing...

 

[jackinnj]

another application for copper foil

copper foil is not only useful in running groundplanes, but also in application such as this.