----- Original Message -----
From: "Dan Kovatch" <firstname.lastname@example.org>
Sent: Wednesday, February 03, 2010 7:34 AM
Subject: [RFI] LED light bar RFI
>I have several nice LED light bars as under cabinet lighting. Very
> power wise but they make more RFI across all the bands up through 6 meters
> than the old switching supply I had with halogens. They use a 'constant
> current' wall wart type supply and replacing them with a linear
> supply causes low light output probably because of the lack of constant
> current. Another LED bar across the kitchen (different make) has no issues
> with noise.
> I have tried ferrite beads to no effect. Has anyone had luck taming these
> Dan W8CAR
After trying all the ideas presented here and from other sources I still had
not conquered the RFI from the 'wall wart' noise generators. After winding
wires both input (AC side) and output (DC to LEDS) around appropriate cores
I went searching on Jameco for constant current supplies. I found one that
had 1.1 amp output-enough to replace all three of the wall warts. I ordered
it figuring that even if it made noise the extra space I gained back by not
having the warts in the way (the new supply mounts under the cabinet like
the lights) I would still be ahead.
The final result is NO discernable noise on any band-especially 160 where
they wiped out my rcvr antennas completely. I post the model numbers and
manufacturers below in hopes it may save someone else some future hassel.
The wall warts are from MDL corp p/n 319-00047 led power supply direct plug
in 350ma constant current, 35VDC (the actual voltage measured around 28DC)
The replacement is a Meanwell LPC-35-1050 (9-30VDC @1.05 amp)
My wife is happy, the roll of tape in the kitchen is happy and most of all
stubborness and technology have once again been put into harmony.
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