The largest EMC/RFI hole with the FCC these days is their lack of enforcing
the regs. already on the books. Part 15 is pretty much ignored and nothing
much stops SMPS from China. And not to mention the whole solar power
industry.
But you've read all this from me before, many times.
Dave - WØLEV
On Mon, Apr 11, 2022 at 11:55 PM Jim Brown <jim@audiosystemsgroup.com>
wrote:
> The gaping hole in FCC EMC regs is that they fail to consider conducted
> emissions on anything but the power line. Thanks to widespread "Pin One"
> problems at connectors for signal and control lines, common mode current
> on these cables, usually on cable shields) is a primary cause of EMC
> issues, both incoming and outgoing. The "Pin One Problem," first
> identified by an engineer with a ham background working in pro audio, is
> the failure to terminate cable shields to the shielding enclosure at the
> point of entry. A similar problem often occurs when the "green wire" of
> the power line fails to contact the shielding enclosure directly at the
> point of entry. The first two links were written for a newsletter for
> sound contractors. The third is my tutorial for hams. The Pin One
> Problem is addressed beginning on Page 8.
>
> http://k9yc.com/Pin_1_Revisited.pdf
> http://k9yc.com/Pin_1_Revisited_Part_2.pdf
> http://k9yc.com/RFI-Ham.pdf
>
> Neil Muncy's original work on this was published in the June 1995
> Journal of the Audio Engineering Society, which can be downloaded from
> aes.org (modest fee). JAES is in the engineering libraries of most
> universities.
>
> 73, Jim K9YC
>
> On 4/11/2022 3:39 PM, David Eckhardt wrote:
> > It was the ONLY product in my some 30+ years as an EMC/RFI engineer we
> > had to install a 35 dB, yes, you read correctly, 35 dB attenuator (!!!)
> > between the product connection to the AC power (LISN) and the conducted
> > emission receiver.
>
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> RFI@contesting.com
> http://lists.contesting.com/mailman/listinfo/rfi
>
--
*Dave - WØLEV*
*Just Let Darwin Work*
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