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Re: humor, was:Re: Transformers for sale



Original poster: "Ed Phillips" <evp-at-pacbell-dot-net> 

"That is a mighty impressive record for coiling longevity.  Do you
remember
any details of your original coil? Did you take any photos with your
digital camera and put it on your web site at the time?
My coiling extends back to 1972 - a mere 32 years ago. Pics on my site.
Old coilers don't die they just .....keep on sparkin'.
Peter (Tesla Downunder)"

	Let's see what I remember.  The original coil I built didn't work at
all because I didn't know anything about tuning and the capacitor was a
single plate of glass.  It was a "bipolar coil" and had a winding on a
cardboard mailing tube about 1-1/4" diameter and about 18" long.
Shellacked (is that a word?) first then wound on a lathe (courtesy of my
dad) with very fine dsc  wire from "country phone" ringers, courtesy of
a pile of phones in the basement of the local phone company.  You could
carry away all you wanted with dry cells, magnetos, oak cases and the
works.  I think people pay money for them as antiques these days.


	Back to the coil.  The primary was about 4" diameter and 4" long, wound
with an unremembered amount of bell wire.  Can't remember the spark
gap.  This was built about the spring of 1939 and set aside when it
didn't work.  Later I saw a demo of a unipolar coil at a University of
Missouri Engineering School open house (my dad was an ME prof there)
which inspired me to make a conical primary wound on 8 1/4" dowels stuck
in a piece of wood and wound with may 10 turns of #18 bell wire sans
insulation.  I cut the old secondary down to about 10" and made up an
8-plate (about 6" x 8") glass capacitor with thin aluminum for the
plates.  That and a spark gap I can't remember worked and gave about 1
to 2" streamers from a needle stuck in a wooden plug on top of the
coil.  I'm sure the primary was way too high in frequency but I didn't
know better until later.  The power came from an NST which I still have,
although it's shorted.  I'd guess it was about an 7.5 kV 30 ma job but
it never had a name plate when I had it.  That's about all I remember.
I still have the primary and secondary kicking around somewhere and have
been looking for it.

	There's also a larger secondary around here somewhere which was made a
few years later.  It is on a 2" mailing tube and wound with dsc wire
which came out of the secondary winding of a Thordarson 1 kW spark
transmitter transmitter which someone gave me.  He just gave me the
secondary for some strange reason and I pulled the wire off without a
thought.  In looking back I think the rest of the transmitter sat on the
ground behind his garage for many years.  He was an old time ham and
probably had the rest of his old spark station kicking around but I was
too innocent to ask about it.  Sure wish I had that transformer now!

	That's about it.  A lot has happened since then and I've moved around
the country quite a bit so don't have much left from those days.

Ed