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Re: Pertronix



Well now that the gauntlet has been thrown down here's my take on it. 
Here's how I would do it.

We'll take the same starting assumtions
600 RPM
fire 20 times over 20 degrees
dwell for 70 degrees 
repeat

600 REV    10 REV     3600 degrees
------- = -------- = --------------
  min       sec          sec


which means that it covers 1 degree in  1/3600  seconds

so therefore when it is traversing the 20 degrees in which it fires it
will be firing every 1/3600 of a second or 3600Hz (3.6MHz) which is
definately RF.

I knew something had to be wrong when you came to the conclusion that my
crank took 2 seconds to rotate 20 degrees.

Since I used to teach math I can't resist this:

Tom Harais wrote:
> 600 RPM / 20 "degrees of spark" per fire event which is 1/30th of a
> revolution (30X20=360)
actually it is 1/18th of a revolution 18x20=360

> which happens in 1/30th of a minute at 600 RPM. 
actually it happens in 1/180 of a second. There 18 20 degree segements
in one rotation and these rotations happen 10 times a second (or 600
times a minute) giving use 
18*10=180 of these 20 degree segments in a second 
or
18*600=10800 of these 20 degree segments in a minute

> So you get 20 "fires" or pulses in 1/30th of a minute. 
20 fires in 1/10800 of a minute

> > 1/30th of a minute (60 sec/min / 1/30 min) so you can say you are getting
> > 20 fires in 2 seconds or 10 fires per second.

20 fires in 1/180 second or 3600 fires in a second

Q.E.D.


Peace,
Eric

-- 
Eric Hegstrom                          .~.
Senior Software Engineer               /V\  
Sonoran Scanners, Inc.                // \\          L I N U X
ehegstrom@domain.elided        /(   )\  >don't fear the penguin<
520-617-0072 x402                     ^^-^^



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