On Tuesday, 2 April 2019 02:56:48 UTC+1, wrote:

Well, they are mostly CCFL. Of course they have Royers in them and they generate EMI. I got an HP339a and to find its measurement flkoor of 0.0016% I had to connect the output to the input with wires as straight as possible.. Using anything else it picked up too much noise, even with the filters on..

Then I am working on a scope and the trace is fat, I pull the arm light away and it flattens out. I turn off all the lights and I got the flatline I should.

So now I got a halogen in the arm lamp, which helps. I also still have the ability to shut of all the lights and have everything else still work. Even with the rest of the lights farther away it still has noticeable EMI.

The halogen is alright but it gets hot. that is inefficiency and not much though because it is like 50 watts. But it makes the shield on my arm lamp hot and that is not only not nice now, any heat generation in the summer is no good here. We don't even use the oven. This is a BIG house and when that A/C comes on it is over a buck an hour to run the compressor.

I wonder now about LED lighting. I know it runs on a couple of volts, and if they are downconverting it it is surely switched mode. Or is it ? They would not just use a resistor, trying to be efficient.

If LED lighting does not emit much EMI I will consider changing to it. This place is bad enough with the bad wiring, yes I know I have to take care of that but still, that EMI is not what is coming form the light bulbs. But what is is up close and personal.

What y'all use for that ?

LEDs, if run on dc, are as clean as it gets. Of course commercial lightbulbs all use switchers, not known for being EMI-free. Roll your own. Ebay has very cheap reject less power than claimed flat panel LEDs, or just rewire a lightbulb.


NT