From my long but now somewhat ancient experience, a major problem with
regulating conducted emissions is that compliance is measured under very
specific conditions using line stabilization networks which may not have
much relevance to the real world environment in which they will be used.
Devices may be compliant but still cause havoc.
On Sat, Nov 23, 2019, 6:56 PM Dave Cole <dave@nk7z.net> wrote:
> Dave,
> The slides were not attached, can you send them directly to me please, I
> would like to see your presentation.
>
> 73, and thanks,
> Dave (NK7Z)
> https://www.nk7z.net
> ARRL Volunteer Examiner
> ARRL Technical Specialist
> ARRL Asst. Director, NW Division, Technical Resources
>
> On 11/23/19 3:27 PM, David Eckhardt wrote:
> > Quate:
> > "cable shields are improperly terminated to the circuit board
> > rather than to the shielding enclosure."
> >
> > This is the NUMBER ONE error the latest crop of designers make. The best
> > way to violate the Faraday Cage they believe they have (had). In so
> doing,
> > THEY'VE VIOLATED MR. FARADAY ! ! !
> >
> > If the neighbor is causing interference, it is radiated from the
> neighbor's
> > house wiring into the ham's antenna. This is especially true if the
> > source is blocks away. However, within the house, yes, the problem is
> > conducted 'emissions'. Attached are thre slides I did for a course I
> once
> > offered. Have a look at the enclosure.
> >
> > Dave - WØLEV
> >
> > On Sat, Nov 23, 2019 at 7:13 PM Jim Brown <jim@audiosystemsgroup.com>
> wrote:
> >
> >> On 11/23/2019 9:18 AM, David Eckhardt wrote:
> >>> Radiated emissions (typically what causes hams interference) is
> regulated
> >>> and levels specified only at and above 30 MHz. Below 30 MHz, 150 kHz
> >>> through 29.99999.... MHz, conducted energy is specified and measured.
> >>
> >> This is NOT correct. CONDUCTED emissions are the primary cause of RFI at
> >> all frequencies, but especially below 30 MHz, through a mechanism first
> >> identified in the world of pro audio as "The Pin One Problem," whereby
> >> cable shields are improperly terminated to the circuit board rather than
> >> to the shielding enclosure. The same error is also quite common with the
> >> Green Wire for power wiring.
> >>
> >> Detail on this at k9yc.com/publish.htm
> >>
> >> 73, Jim K9YC
> >> _______________________________________________
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> >> RFI@contesting.com
> >> http://lists.contesting.com/mailman/listinfo/rfi
> >>
> >
> >
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