Recently some forum threads have come up about how the current draw on a strobe is different than a string of lights, the electrical noise it generates, and how it can have an effect on LOR.  Lets start with a simple example of a string of incandescent lights:

  The taller curve here is the line voltage at the house.  It should be a smooth sine wave, but there is obviously some distortion from all the computer and other electronic power supplies in the house.  The shorter curve is the current measured in the string at the same time.  You can see that current goes to zero at the same time that voltage goes to zero, and that there is a constant ratio between voltage and current, which would be consistent with Ohms law of V=IR, so as measured here, this is a pure resistive, linear load.  The photo should be a link to a brief video of the same, so you can see that this is not changing over time.

Here is a photo of the same measurements for a single strobe light:

 The first thing I would note here is that the peak current does not remotely line up with the peak voltage.  In fact, current is leading voltage.  There is positive current while voltage is still negative, and current is not zero while voltage is zero.   Note that the first stage of one of these strobe lights is a voltage doubler, just like the input stage of the 2008 CDI LED light strings.  They may well have had steady state current input that looked similar to this.  If you click on the photo to view the video, you will see that this wave form actually changes as the strobe charges and fires.  The start of current draw gets later as the strobe charges, and gets closer to firing.  Once it fires, the start of current draw moves back to this early point, and the cycle repeats. 

Here is the same measurement set for 10 of the strobes on the same channel:

Note how variable the total area under the curve is in either of these cases.  That relates indirectly to how variable the current draw is on these lights.  Also, any point on these wave forms with sudden bends in the curve are points that cause harmonics and electrical noise propagation.  The incandescent case is a fully smooth wave form that only propagates 60 Hz hum.  These wave forms from the strobes generate a bunch of different frequencies that will be radiated.

While I was set up to do this, I took a look at a group of LED strings:>