Arc AAA switching noise

I noted a difference between the Arc AAA LE that I own and some other regulated LED light. If you put a PT Matrix LED Head or an Opalec NewBeam close to an AM radio, you can ear the electromagnetic noise coming off the inductive type of step-up regulator. The Arc AAA is totally silent, even at higher frequencies, and this may be regarded as an additional bonus. Does anybody know how step-up regulator works in Arc AAA? I have been able to make capacitor - diode type of inverter that radiates no RF, but they have a painful low efficiency...
Anthony

The Arc may just be better shielded.

i think paulr is right.

And I third that notion. /ubbthreads/images/graemlins/grin.gif
Anything that uses a transistor/inductor step-up will produce some radio noise, but I believe the metal casing of the Arc shields most of that and stops it from getting to the radio antenna.

How does the PT Matrix LED compare to the Opalec? I'm thinking the Matrix is dimmer from its advertised runtime of over a hundred hours. I think a hundred hours is a bit too much of an exaggeration, hm?

I think Craig has the answer. My plastic bodied Shorelite and Sauce Light Wand cause terrible interference on the AM band.

Some of those high-frequency devices are horribly noisy.

I have a small four-AAA NiMH AC charger that has a high-freq converter inside. It will take my wireless ethernet LAN off the air if plugged into the same AC circuit as any of the nodes ... /ubbthreads/images/graemlins/ooo.gif

Arc AAA is using step up converter that the frequency is higher than the AM band /ubbthreads/images/graemlins/smile.gif