Your flashlight likely has a DC-DC converter in it to keep the light
output relatively constant as the battery voltage drops. That would be
the source of the RFI. It's also possible that the LEDs are multiplexed
so that one won't hog all the current as they would if parallel
connected. That also could create considerable RFI. Although the RFI is
radiating from the components you mention, they aren't its source.

Roy Lewallen, W7EL

John Smith wrote:
I have a high-power LED flashlight, 5 superbright leds in the element... it
is bright, if I bring it near an AM radios I lose all reception... this rfi
is solely the product of the leds, the connecting wires and the
batteries--the flashlight housing is aluminum...
I have never checked just how large a bandwidth the rfi covers...

Regards,
John