I did some research and Maxim makes ICs for offline LED lamps such as the
Home Depot lamps. The switching frequency is 50 to 330 kHz and the
incoporate frequency dithering to reduce EMI.
The standard they adhere to appears to be EN 55015, Limits and methods of
measurement of radio disturbance characteristics of electrical lighting and
similar equipment.
I found a plot of the limit line and it is in dBuA. In the 160 meter band
it is 28 dBuA. From what I gather a standard 50uH/50 ohm LISN is used for
the measurement.
The standard applies from 9 kHz to 30 MHz.
Dave WX7G
On Apr 6, 2012 5:02 PM, "Garry Shapiro" <garry@ni6t.com> wrote:
> George,
>
> I suspect your question at the end was tongue-in-cheek. We know from
> long experience with other notorious consumer noise sources---e.g.
> plasma TV's, cheap dimmers, touch lamps, fish tank heaters,
> thermostats--that the FCC has been neither active nor timely in
> exercising its enforcement prerogatives. Some of this is probably due to
> the disparity between congressional mandate--i.e. "do this"--and
> funding, but we have had little indication of the government's interest
> in pursuing Part 15 violations, especially against imports of dubious
> quality.
>
> I fear we are facing a tsunami of RFI, speeding toward us as a perfect
> storm of "modern" lighting. I have in the past laid in a supply of
> relatively quiet dimmers and replaced many in the neighborhood. But CF
> and LED bulbs will be ubiquitous and it is likely to be impossible to
> deal with this problem---unless we can generate pressure on the FCC to
> enforce Part 15.
>
> Garry, NI6T
>
> On 4/5/2012 4:10 PM, GeorgeWallner wrote:
> > On Thu, 5 Apr 2012 16:01:12 -0400
> > "Mike Greenway"<K4PI@BELLSOUTH.NET> wrote:
> >> I wondered how long it would take before they started
> >> selling some RFI
> >> generating lighting. Soon we can have a complete
> >> neighborhood of RFI
> > I have tested compact fluorescent bulbs a couple of years
> > ago and found that they were noisy. I have not tried to
> > quantify the level of noise emitted, but it was about S5
> > on my K3 at a distance of about 4 feet using a one foot
> > wire for antenna. I have stayed with incandescent, but my
> > neighbor has installed over 50 of them on his house. The
> > noise coming from that direction (NW) is significantly
> > stronger than what I get from any other direction. Since
> > he has installed the CF (and many LED) bulbs, I have not
> > made one JA QSO! Fortunately, my DHDL, which looks towards
> > EU (NE) completely blocks the noise and I am still able to
> > work Europe.
> >
> > On the other hand, I have LED lights installed on my dock,
> > which is only about 20 feet to the East of the RX antenna,
> > but these LED lights are driven by well filtered drivers
> > in metal boxes. No noise from these lights can be
> > detected.
> >
> > It seems to me that we have a very serious threat from
> > noisy "switched" light sources (and other digital noise
> > generators, like Variable Frequency Drives) that have not
> > been properly filtered. I am wondering the if the LED
> > bulbs bought from Home Depot meet FCC Part 15 specs. Were
> > they marked so?
> >
> > George, AA7JV
> >
> > _______________________________________________
> > UR RST IS ... ... ..9 QSB QSB - hw? BK
> >
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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