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Old 01-06-2011, 02:31 PM
Unclenick Unclenick is offline
 
Join Date: Nov 2010
Posts: 1,072
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No, it's not way off. You know a time base is in there somewhere. But the readout is bullet speed, not time or time intervals. That's why I think of it as a speed meter.

I did build and sell a few breakwire ballistic stop watches at gunshows back in the early 80's. Also messed with, but never sold (too much trouble) a conductive ink pattern silk-screened onto paper to replace the wire. They and the wires were on a PVC pipe frame that set the spacing. Slow work and some bother, but it functioned OK. 4 MHz crystal time base, just as is commonly used today, chosen based on the counter chip's limitations. I've still got one in the basement somewhere. I should probably take a photo to show how technology has advanced.
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