"Steve" wrote
| My curiosity knows no bounds, it appears. When I bought one of
| those LED cycle lights, I hooked up a sillyscope to it and
| discovered that on the "steady" setting, it actually spent 3/4 of
| the time switched off. 100 Hz square wave mark to space 1:3.
| The mean brightness is still the same, since the mean current must be
| the same, because you can't leave the LED on at the current used when on
| or it will burn out. However driving them switch mode allows the circuit
| to run more efficiently which IS why they are pulsed.

Is there a certain frequency above which this pulsed light is considered a
continuous light and therefore acceptable as the continuous light required
under the Road Traffic Act or whatever legislation says that flashing lights
on bicycles are verboten?

Owain