Well, I've been reading the responses, and all I can say is if you are dealing with a product that will absolutely draw a constant rate of power for all time, then you should see no variation *from the product* unless of course you're in some varying unreliable environment, or the product and/or something on the product is mechanically moving.
But as soon as you begin to use digital signals that gate/enable devices, refresh memory, poll lines, read and write to and from memory, etc... you move from perfectly repeatable periods of signals to non-perfect non-repeatable periods and open yourself up to all sorts of effects - beat freqs, image freqs, etc, and ultimately varying power at some level the resolution of which is ultimately decided strictly by the signals involved and what they are doing. Just the issue as regards to variation of amplitude, this indicates to me and I'm sure everyone here obviously varying power for whatever reason. Now, I've seen at least what I think you're describing on equipment. But over time, it could be correlated to all sorts of things going on inside the device. That involved a very detailed analysis of the product. It's my gut feeling to doubt that it's truly *random* variation of amplitude, but you of course would know the answer to that much better than I and of course does not in any way mean that I doubt what you are seeing. I have seen some strange stuff in my time. There's my 2 cents... Regards, Doug ---------- > From: mvald...@netvision.net.il > To: emc-p...@ieee.org > Subject: modeling RFI sources "randomness" > Date: Saturday, September 14, 1996 1:02 AM > > Hello everyone, > > As we know, while measuring RFI generated from a product at a specific frequency, we get > randomly changing amplitude (and I guess phase is also changing with time). This is why > "peak", "average" and "quai-peak" are different. > > On the other hand, the sources of interference (e.g. conductors running clock signals) > are fixed and one would expect them to radiate a fixed signal. > > What is the explanation for this effect? (I.e. is there a model describing what > influences the radiation generated?) Was there academic work in this area? > > thanks > > ------------------------------------- > Name: moshe valdman > E-mail: mvald...@netvision.net.il > Phone: 052-941200 > fax: 03-5496369 > Date: 13/9/96 > Time: 22:02:44 > You are most welcome to visit my homepage at: > > http://www.geocities.com/CapeCanaveral/5233/ > -------------------------------------
