Ed, That's about it. As Yogi Berra once said, "You can observe a lot just by watching". However, we do not watch for EMI emissions systematically. Unless the beginnning of the time averaged measurement is synchronized with a re-occurring event in the equipment, each measurement may give a different reading. In this case, it is not the emissions that are random, but the "random" way we measure it.
If one plotted the amplitude of every frequency with time, they would see a
repetitive pattern emerge. Randomness, on the other hand, implies changes
with no order or logical
cause.
George Alspaugh
(Embedded
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PIC06570.PCX)
Please respond to ed.price%[email protected]
To: emc-pstc%[email protected]
cc: (bcc: George Alspaugh)
bcc: George Alspaugh
Subject: Re: Randomness vs. Order
> In my opinion there is no randomness to EMC emissions. Every moving
> electron results in an electromagnetic emission. The electrons do not
> move randomly. A device may create the exact same emissions at
symmetrical
> or asymmetrical intervals. This can give the appearance of
"randomness".
>
> George Alspaugh
> Product Safety Authority
> Lexmark International
---------------End of Original Message-----------------
So what you are saying, George, is that, if it looks random, you ain't
observed long enough!
--------------------------
Ed Price
[email protected]
Electromagnetic Compatibility Lab
Cubic Defense Systems
San Diego, CA. USA
619-505-2780
List-Post: [email protected]
Date: 09/18/97
Time: 12:58:47
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