Not to mention that these do not appear to be UL/CSA listed. As far as
I know it is illegal to sell these in Canada.
Run away as fast as you can!
Steve W7SJK
> Date: Sun, 23 Jan 2011 03:46:25 -0800 (PST)
> From: Craig<vk3he@yahoo.com>
> Subject: [RFI] LED Floodlight warning!!
> To: rfi@contesting.com
> Message-ID:<301832.98313.qm@web161206.mail.bf1.yahoo.com>
> Content-Type: text/plain; charset=us-ascii
>
> 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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