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Re: [RFI] Switching Power Supply test Video

To: rfi@contesting.com
Subject: Re: [RFI] Switching Power Supply test Video
From: Cortland Richmond <ka5s@earthlink.net>
Date: Sun, 7 Aug 2016 18:24:52 -0400
List-post: <rfi@contesting.com">mailto:rfi@contesting.com>

Since reception depends on uncontrollable parameters of propagation, antenna system and receiver performance, adjacent-channel rejection, etc., there are NO quantified definitions of harmful interference -- and Part 15 doesn't guarantee there won't BE any harmful interference.

From Part 15.3:
(m) Harmful interference. Any emission, radiation or induction that endangers the functioning of a radio navigation service or of other safety services or seriously degrades, obstructs or repeatedly interrupts a radiocommunications service operating in accordance with this chapter.

And from Part 15.15
(c) Parties responsible for equipment compliance should note that the limits specified in this part will not prevent harmful interference under all circumstances. Since the operators of part 15 devices are required to cease operation should harmful interference occur to authorized users of the radio frequency spectrum, the parties responsible for equipment compliance are encouraged to employ the minimum field strength necessary for communications, to provide greater attenuation of unwanted emissions than required by these regulations, and to advise the user as to how to resolve harmful interference problems (for example, see §15.105(b)).

Check out http://www.commlawblog.com/2009/01/articles/broadcast/finding-the-harm-in-harmful-interference/

I've suggested measuring SNR when interference is both present and absent, this being the closest we can get to an objective test; the ITU has published SNR's requred for grades of service using different modes.

Cortland Richmond
KA5S
EMC since '83.

On 8/7/2016 3:54 PM, Michael Coslo wrote:
Unfortunately, it is not always possible to get meaningful results with 
meaningful defined as tightly controlled laboratory conditions. I would love to 
see the work that has the lab results.  Anyone have the cites or could grant 
access to their own work in this area? It would be especially helpful to see 
the tests done on the

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