USB Stuff

I actually wouldn't worry about that, for two reasons: (1) they have a relatively long "on" time (partly the long-persistence phosphor, partly the width of the mains voltage peak), and thus a rotating lathe, even if rotating at a multiple of the strobe rate, will look blurred rather than stationary, and (2) anyone who depends solely on the appearance of the moving parts to tell whether a lathe is on is so stupid as to have no business near power machinery in the first place (look at the power switch, listen for the motor, find a smooth rotating part and touch it lightly, the ways to tell are legion). I even went so far as to try this. I turned out everything but one compact fluorescent and got out my (variable-speed) electric drill. The chuck has three holes for the chuck key and thus should "appear stationary" when spinning at 20 rps (1200rpm, the drill's rated top end) - remember I'm on 60Hz mains power. :) No matter how I fiddled with it, I couldn't see any trace of the strobe effect, not even the sort I'd expect if it were spinning at half speed and I'd thus see two ghosts instead of one steady copy. Just blur. I also can usually see strobe effects when I wave my hand fast in front of flickering lights like large areas of white on a CRT. I was unable to produce more than the barest trace of that effect with the compact fluorescent. Still, if it makes you more comfortable.... :-) /~\ The ASCII der Mouse \ / Ribbon Campaign X Against HTML mouse at rodents.montreal.qc.ca / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B