[RFI] "No RFI" LED bulbs

Jim Brown jim at audiosystemsgroup.com
Tue Aug 15 19:25:57 EDT 2017

I suspect the RFI problem is caused by a poor quality power supply, or 
the use of AC to drive the LED directly.  I've used a lot of the LED 
strips that Wired Communications sells at hamfests, mostly in the 
western US. I use five of them to light my shack, powering them from the 
12V battery that is float-charged from a linearly supply.

Last month, I mounted two strips on a shelf to light the area around my 
computer desk, and, by accident, grabbed a 12VAC wall wart (in other 
words, just a transformer) to power them. The RF noise was VERY strong. 
Replaced the transformer with a 12VDC linear supply and the noise went 

Of course, a switch-mode power supply would also generate noise.

73, Jim K9YC

On 8/15/2017 4:08 PM, Ken Winterling wrote:
> I have also heard some reports that the fluorescent or LED bulbs in an
> opener can cause trouble with electric car door locks.  Some folks had
> difficulty locking/unlocking their car doors while the opener lights were
> lit.

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