I hope and pray our U.S.A. FCC is on the ball with upcoming LED lighting. This
is most concerning as I am beginning to see LED floodlights at our local Home
Depot. The LED floodlights that I've seen are priced at about $30 US and look
like the old floodlights. They screw into standard floodlight sockets. I've
not tried one yet, but as I said, I hope the FCC is on the ball and prevents
anymore rfi junk to be sold here. It's bad enough as it is.
Thanks for the tipoff Craig.
73
Dale, k9vuj
On 23, Jan 2011, at 5:46, Craig wrote:
> Hi All
>
> I recently purchased this new LED floodlight which has turned into a RFI
> nightmare. I just want to warn other hams about the huge amount of
> interference that these lights cause.
>
> My warning might also help those looking for interference sources around
> their neighborhood. LED floodlights are a disaster as big as bad plasma TV
> sets because the QRM level is so intense.
>
> These light are becoming popular because they can save you a lot of money
> when compared to running a normal 500 watt floodlight.
>
> I purchased several of these LED lights from various Ebay sellers. They all
> seem to originate from the same factory. They have ratings from 10 to 50
> watts. These lights are the ones that use a huge large LED CHIP rather than
> discreet individual LEDs
>
> Here is a link for one on Ebay, if it looks like this light avoid it.
>
> http://cgi.ebay.com/Lemansind-50W-White-LED-FloodLight-Wall-WashLight-/270694205505?pt=US_Flashlights&hash=item3f06a1c841
>
> A generic search for "LED floodlight" will show the many seller listings for
> these lights.
>
>
> These light cause S9+20db hash right across the HF spectrum. Its the worst
> case of switch mode power supply noise that I have ever encountered. What
> also amazes me is the strength of this hash that could be detected from a
> long distance away, upto 1km away!
>
> I emailed the supplier, and he advised me that he has paperwork which
> certifies the lights with a C tick compliance. The paperwork is obviously
> fraudulent or he is just telling lies. Most of the goods from China have
> fake EMC compliance documents and certification ..
>
> When I opened the light, it had a small switch mode power supply module. This
> module does not appear to have any mains filter or other output filtering.
> The light is well shielded since the whole assembly is cast aluminum. The
> power supply module is well shielded, hence the surprise at the rather high
> noise levels.
>
> I added a IEC filter which did nothing to reduce the noise level. I added 2 X
> Fair-rite FT240-31 ring cores on the power supply lead and this did not help
> either. I added 2 X #31 material cores onto the DC output and this did
> help, however the noise was still shocking.
>
> I am going to try some capacitor bypassing and perhaps a professional DC
> filter. So far the signs are not encouraging. The noise is still very
> intense. If I dont have luck I will just throw these lights in the bin.
>
> I have these lights in 10 20 and 50 watts and they all have the same
> interference levels. Its a real shock to turn on my SDR receiver and see the
> waterfall go red(5/9+) from 1mhz to 30mhz!
>
> Anyway avoid these lights like the plague!
>
> 73
> Craig
> VK3HE
>
>
>
>
>
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