The radiated and conducted limits are really pretty strong signals if
received on an amateur transceiver. Worse, yet, the industrial limits are
10 dB greater than those for home and small office (Class B) electronics.
If any of us hams had a broadband radiating source that put out -30 dB µV/m
(the FCC -minor adjustments for FCC - and EU limit for radiated emissions
from 30 MHz < F < 230 MHz) from 1 through 30 MHz living next to us and
coupled to the power wiring of the house for an antenna, we would bitterly
complain (I shre would!!). But the appliance, what ever it might be,
conforms to FCC (and EU) standards for RE and CE.
Using 107 as the fudge factor (from my compliance testing) to convert
signal field strength to dBm: -30 dB µV/m + 107 = +77 dBm. That's 3 dB
over S-9 on a properly calibrated S-meter. OUCH If it plays to the
industrial limits, that's 13 dB over S-9. OUCH^2
Dave - WØLEV
On Tue, Nov 20, 2018 at 8:42 PM Kim Elmore <cw_de_n5op@sbcglobal.net> wrote:
> Yes. Consider an industrial plant near an airport that wipes out the ILS
> system or inhibits ATC or law enforcement comms. The section of Part 15
> that says no harmful interference will most certainly come into play as
> the affected users are licensed operations. The exemption lies in the
> radiated field strength (they're neither Class B or Class A devices that
> have field strength limits) but they still may not cause interference to
> licensed operations.
>
> Kim N5OP
>
>
> On 11/20/2018 12:07 PM, Lee STRAHAN wrote:
> > So industrial plants are also exempt from the part 15 requirements
> but does this also mean that they still cannot cause harmful interference?
> >
> > Lee K7TJR OR
> >
> > The FCC has not generally tried to interpret things as appliances that
> are not. The devices are still subject to the requirement that the operator
> of the device not cause harmful interference.
> >
> > Ed, W1RFI
> >
> >
> > _______________________________________________
> > RFI mailing list
> > RFI@contesting.com
> > http://lists.contesting.com/mailman/listinfo/rfi
> >
>
> --
>
> Kim Elmore, Ph.D. (Adj. Assoc. Prof., OU School of Meteorology, CCM, PP
> SEL/MEL/Glider, N5OP, 2nd Class Radiotelegraph, GROL)
>
> /"In theory there is no difference between theory and practice. But, in
> practice, there is." //– Attributed to many people; it’s so true that it
> doesn’t matter who said it./
>
> _______________________________________________
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> RFI@contesting.com
> http://lists.contesting.com/mailman/listinfo/rfi
>
--
*Dave - WØLEV*
*Just Let Darwin Work*
*Just Think*
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