[sdiy] Shielding

[harry bissell]

Hi Lava

The rule for EMI is you have a source, a receiver, and
a medium for transmission.

step one is to identify those three items. What makes
the noise, what recieves the noise and how does it get
from point 'A' to point 'B'.

Then you see what you do about it. You might shield
the source. You might interrupt the medium... you
might shield the receiver.

Some noise rides on the cables and power lines...
usually things like line filters or ferrites can help
there.

Some noise goes through the air... in that case you
might want to use a sealed metal box with no open
holes of cracks. The wires would be run through
filtered connectors.

Another Idea is to re-orient the transmitter or
receiver to get rid of the problem.

If it is switching noise that is the problem, you
might
make a linear supply... it will be BIG and HEAVY.

Also watch out for the backlight on the display...
some of the fluorescent lamps can emit RFI also.

H^) harry




--- Moho Disco <moho at mohodisco.com> wrote:
> How does one go about shielding something?
> Say, a line lump laptop power supply?
> 
> Thanks,
> 
> Lava
> 
> 
> 


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