Re: secondary comparisons

[FutureT-at-aol-dot-com (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

In a message dated 9/5/00 11:49:34 PM Pacific Daylight Time, tesla-at-pupman-dot-com 
writes:

> Original poster: "Metlicka Marc" <mystuffs-at-orwell-dot-net> 
>  
>  hi all,
>  a status report and a question.
>  the primary for the 3k turn secondary is awaiting 100' of 1/8" copper
>  tube to arrive from mc master car. it's funny how you can see coils of
>  the stuff in every store you go into until you need some? but it should
>  arrive by thursday and i hope to fire first light by Saturday?
>  my question is, since i really don't see anyway to make a direct
>  comparison to the added turns, i was wondering if maybe a comparison for
>  diameters increasing output would help? my thinking is that if i was to
>  wrap a 10" form too 32.4" length, using the same wire (28g) this would
>  give me 378mh inductance. 8mh difference from the 8"-at-40" secondary, also
>  this would give me 37.37khz on the 10", .03hz difference from the 8"
>  coil. all other things being equal between the two.
>  has anyone done a comparison of this? would it be of interest to anyone?

Marc,

A comparison of different diameters is of great value, although it
suffers from the weakness that many parameters change when
you try to change just one parameter.  The fact that many parameters
change does not eliminate the value of the test, it just makes it 
harder to attribute the results to a particular cause.  But you will
still know if such a design is better or worse.  Other subsequent
tests can try to pin down the exact cause. 
>  
>  i really wanted to show any benefits of double the turns from the norm
>  but, as many have tried to think of a way to do it, with more astute
>  minds then i possess, it seems there is no easy solution.
>  any info on the pro's or con's with this will be greatly appreciated,
>  thank you in advance,   mem

I think there is great value in simply doing a test by doubling the
turns, since you will know if such a design is better or not.  Again,
you might not know the exact cause of the improvement.... but you
will know if it's better or not.

JOhn Freau
>