No flame throwing in the following:
I've asked this before, but I'll pose the question again:
What constitutes "harmful interference" and how does one put a quantitative
and consistently measurable method and tool in place to make that
measurement?
In the 1950's FCC placed field strengths with limits on that parameter and
measurement methods which, at the time, were intended to represent "harmful
interference". In the mid to late 70's the limits became more restrictive
as the digital age began to break (remember the 5 and 10 MHz 'scream'n PC
clocks?). Not only does FCC have in place field strength limits, but a
"filter" to equivalence *all* kinds and types of RFI with a single time
constant (the QP average "filter" which amounts to a post-detection LPF).
Nothing has changed since then. Suppliers and manufactures have taken
advantage to dodge these measures by employing spread and random sequenced
clocks which subvert the rules and limits presently in place from the FCC
by spreading all the energy out over a distributed bandwidth. Further,
there are no regulation on the solar power industry, in general. Times
have changed in a huge way since the late 70's to early 80's!!!!! FCC has
not updated anything in that respect that matters to the "low life" that
inhabit the RF spectrum (that's us amateur radio operators among the many
other users of the RF spectrum).
As an EMC engineer of some 40+ years, I contend the field strength
philosophy and approach to putting a cap on "harmful interference" is no
longer applicable to assessing and measuring "harmful interference" in the
digital-everything world of today. But it would take an act of congress
and a flip of the magnetic poles of the earth for anything to deviate from
the established field strength philosophy and the time constant dictated in
the QP "average". Oh, yes, and maybe revisit the QP "average" filter and
measurement.
S-9 as we all should know is -73 dBm or -103 dBW. What is S-9,
specifically, to Jessica??!! All of us know S-9 on even an uncalibrated
(pre-SDR's) S-meter is NOT a weak signal!!! I believe she just pulled that
out of her hat. Just my editorializing on the present incompetence of
FCC.
Dave - WØLEV
On Sun, Dec 18, 2022 at 7:58 PM <wx5l@charter.net> wrote:
>
>
> There have been comments that the ARRL has the FCC's ear. Really do they?
>
> Recently Jessica Rosenworcel , FCC chairwomen has made a statement about
> issues with Solar Edge RFI and said that S-6 to S-9 is NOT harmful
> interference. On what basis can she make that determination. Does she know
> what an S unit is? Has she been advised from a technical support group to
> make that comment?
>
> The FCC's should not label harmful interference with an S-meters
> reference.
>
> I would be confident to say of there would be s-6 interference to a fire
> department, ambulance service or aircraft control tower that would not be
> tolerated but as amateurs we must tolerate it in the eyes of the FCC.
>
> Now let the flame throwers commence.
>
> 73,
>
> Randy
> WX5L
>
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> http://lists.contesting.com/mailman/listinfo/rfi
>
--
*Dave - WØLEV*
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