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Eureka! It's Alive! a S.N. transformer is born. (Super Neon)



Original poster: "Duke, Ronn (CCI-San Diego CCC) by way of Terry Fritz <twftesla-at-uswest-dot-net>" <Ron.Duke-at-cox-dot-com>

Greetings Terry, and all you list surfers,

Many of you have probably noticed my progress and comments on rewinding a
15/60 Franceformer. Well I finally did some testing with analog meters on
the performance, (no fancy oscilloscopes here), and here are the results.

First let's start at the beginning. This will be review for some of you.

 I am still in the process of building my first coil, (6"x30" hope to have
it up by holloween), I've noticed after being on the list for a year, that
the neon graveyard is getting overpopulated. My intention was to see if I
could build a better mouse trap. I acquired my NST's for free (I have 8-
15/60 Franceformers) from a local neon shop. I wanted to unpot one to
enhance it after reading how to do it from the archives. Is a 90lb
jackhammer too severe? Well anyway, I decided to use a hammer and a
screwdriver. I ended up putting a nick in one of the secondary coils. Having
more motivation now, I got it apart, I checked the damage which didn't look
to bad. Was I naïve!  27 layers later I had continuity.  I wanted to see if
I could rewind it without the big equipment that the manufacturer uses. I
fashioned my self an automatic feed winder out of MDF shelving(medium
density fiber). This material is strong, easy to work with, and doesn't
crumble like particleboard. It will split if you drive screws in the side
without pre-drilling. I used various wheels and belts from the local
electronic surplus store. I also cut some wheels of my own out of the
shelving a certain size for the lateral feed. (Different wire sizes require
different feed rates). The feed is coupled directly to the spindle. I wound
the coils using 30ga. heavy Nyleze wire( the thickest wire I could use and
still get the number of turns I needed within the space available). In
between the layers I used Kraft paper( 4 mils.) from Home Depot(masking
paper). Oiled, this paper has a dielectric tolerance of about 300v per mil.
I left about ¼ in. at the sides of the paper to prevent flash around. Upon
assembly, I took out all but 8 shunts in each pack(had 22 originally). This
gave me more room for the windings and I still had some current limiting.
For insulation in between the core and the windings I used 10 mil. Mylar
sheeting. This transformer had an internal PFC cap,(4.3uf connected to the
dual primaries). I modified a 30 cal. surplus ammo box to put it into. The
HV terminals are ½ in. PVC with 15kv HV wire from the transformer. Because
of lack of transformer oil, I used a mineral based, non detergent, 30 wt
motor oil to pot it in and that seems to work just fine. 

I wanted to see what kind of voltage I would get out of it, so I connected
panel meters to various parts of the circuit. Using a 30 amp. Variac, I ran
it up to 115v. The line draw was 24 amps and the output was 13,400v at 260
ma. with no flashover or arcing problems. I decided to over volt it a little
to see what it would do. I went up to 125v, the output voltage went to
14,000v -at- 300ma. The line draw went up to 28 amps. Clearly no saturation
problems here, everything was proportional. The line draw seems to be close
to what Ross Overstreet was getting when he was he was testing his enhanced
NST. 
Can't wait to test it in battle. I'll keep y'all posted.

Keep on Coilin'    
Sparky