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Re: (meteorobs) Rotating shutters
In a message dated 96-08-29 18:18:19 EDT, you write:
<< Nope: I appreciate the info! In fact, it'll probably make me think again
about
using your plans, George... Who did you say that fan's manufacturer was? :)
>>
------
It's an Aurora Deluxe Desk 16 inch fan made in China but distributed by Longs
drug stores of Walnut Creek, Cal 94596
other info is that it's model # is: 14B8763
Voltage 120
Frequency 60hz
current 0.8 Amps
power: 80 watts
To tell the truth, I've seen these things all over the place...Home Depot,
Longs Drug stores, Thrifty's etc.
>>I think I've almost got it! You found the blade had a rotation rate of 1150
RPM.
But wouldn't that mean the strobe would show harmonics at 575 FPM (flashes
per
minute), 383 FPM, 287 FPM, etc., etc.???
Harmonics at 650 FPM and (near) 450 FPM make the actual blade RPM sound more
like 1300... In other words, 1300 / 2 = 650, 1300 / 3 = 433, etc. (Sorry to
thrash this one out, but I HATE when I don't get stuff like this right off!
:>)<<
Lew,
Beats me!...I'm just going by what my stroboscope says and I do think it is
within 50 RPM's if not better. I don't really know what may be giving you
trouble in figuring what the rates should be, but for some reason every time
something goes in circles and I can't explain a prediction very easily, it
seems that the value of "pi" has something to do with it...I'm not a math
wizard by no means and I couldn't even begin to guess to suggest why I think
this...just a gut hunch.
George Z.