Iron Coils amateur coating

[Shodan486]

We all know there is some ''noise'' in our computer systems. Iron / Ferrite coil chokes are preventing this to happen at their utmost capabilities, but sometimes (as it has been explained to me) if more of these coils are placed in near vicinity, they actually interfere with each other IF not properly packaged...

So let's take a look into the 90'-late 2004 - The coils were absolutely naked on an average mobo from almost every motherboard manufacturer, which wasn't the best solution for overclockers, thus the circuits could perform inappropriately, in worse cases fail with ugly consequences...So I have an idea (and an impression from Supermicro's mobos) - let's get them some clothes !!!

You may have caught a glimpse of these coils to have some plastic/rubber thing spinned around and over it, helping this to diminish the EMI...

So my point is: Can I make myself something like that for the naked ones? I guess it can help a bit to stabilize the circuitry, so why not to try it? Do I use some plastics or some liquid compund to cover them?

Thanks for your thoughts!!!

[Shodan486]

Re: Iron Coils amateur coating

Here's what I mean:



Circled yellow, the coils have what I'm about to replicate on some of mine. Any suggestions/ideas?

[stj]

Re: Iron Coils amateur coating

your talking about heatshrink sleeving.
and it's there to stop the coil resonating and making a high pitch sound.

[Shodan486]

Re: Iron Coils amateur coating

Thanks, I've already heard this one, so it's probably sure. So there's no way how to minimize the EMI from them?

[stj]

Re: Iron Coils amateur coating

only putting a ferrite tube over them.
but that could change the inductance.

what's wrong with the emi?
it should be contained inside the pc casing.

[Shodan486]

Re: Iron Coils amateur coating

....uh...ehm...how? Really I don't know. Please explain.

[NxB]

Re: Iron Coils amateur coating

Likely no way to stop it. You can try finding EMI shielding material and wrap them but you're making a lot of effort for possibly negligible gain. The wrap on the coils is heat shrink tubing, no effect.

You can buy RF shielded inductors.

http://www.commsdesign.com/new_produ...cleID=16501510

[NxB]

Re: Iron Coils amateur coating

http://news.thomasnet.com/fullstory/561308

[Huckfinn]

Re: Iron Coils amateur coating

From the picture you posted, it appears that the choke coils you are thinking about replacing or improving are the circular torroidal variety. A torroid choke confines its magnetic field to the circular structure, by the very nature of a torroidal coil wound magnetic assembly. I don't think that you have to worry much about a torroidal choke coil radiating much EMI inside the CPU case. I very much doubt that you could actually measure any real performance improvement after having totally magnetically shielded those two torroids with something even as effective as mu metal.

Huck

[Pyr0Beast]

Re: Iron Coils amateur coating

I would agree with that. Some chokes were sleeved to prevent them from 'whining'.

[ratdude747]

Re: Iron Coils amateur coating

hey guys, you might want to post your pics via this forum instead of using imageshack, etc.

that way, we get no bad link symbols.

when posting, scroll down below the text window and click "manage attachments". the rest is self explanatory

[Shodan486]

Re: Iron Coils amateur coating

hey guys, you might want to post your pics via this forum instead of using imageshack, etc.

that way, we get no bad link symbols.

when posting, scroll down below the text window and click "manage attachments". the rest is self explanatory

Affirmative.

[robert]

Re: Iron Coils amateur coating

Toroid coils emit nearly no EMI compared to most any other type of inductor, even "shielded" types are far worst.
The toroid core concentrates all magnetic flux inside, with no seams or gaps where stray flux can form.
When theres plastic sleeving around, it is only used to make assembly easier, carries markings and serves no other function. If an indictor produces audible noise with the wire vibrating, then only encapsulating it in resin will help.