From: Geoff Schecht[SMTP:geoffs-at-onr-dot-com]
Sent: Wednesday, September 24, 1997 3:10 PM
To: Tesla List
Subject: Re: neon rewind
Many NST's are wound with very fine wire, somewhat smaller than AWG40 if
I'm not mistaken. You'll need a spool feeder and wire tensioner of some
kind; otherwise wire that fine will almost inevitably break if you try to
machine wind the bobbin with anyuthing much smaller than AWG34 or so. Hand
winding is less likely to cause breakage but (as you pointed out) that can
take a very long time. Heavier wire, of course, makes the job a bit less
delicate but is your core large enough to handle the additional bulkiness
of thicker wire if you want to maintain the original turns ratio?
I believe that the NST manufacturers use thinner wire than is necessary for
bobbins of a given size to keep the secondary resistance up, thereby
building in some ballasting resistance for the intended neon tubes. You'll
notice an increase in output current if you use heavier wire for the same
number of turns (kind of an obvious advantage).
Let me know what your results are!
> From: Malcolm Watts[SMTP:MALCOLM-at-directorate.wnp.ac.nz]
> Sent: Tuesday, September 23, 1997 2:19 PM
> To: tesla-at-pupman-dot-com
> Subject: Re: Primary Qs
> Hi Jason, all,
> > From: Jason Judd[SMTP:Jason.Judd-at-anu.edu.au]
> > Sent: Monday, September 22, 1997 10:42 PM
> > To: Tesla List
> > Subject: Re: Primary Qs
> > Hi Malcolm,
> > I have a few half dead neons and was wondering about rewinding them. I
> > don't know much about the windings though. How many turns does each leg
> > the secondary have ?. If the ratio is around 1 volt per turn then you
> > need 7500 turns on each side to get 15KV. How are you going to wind it
> > with what guage wire ?
> > Please keep me/us informed with this.
> Wilco. I will be depotting/examining the core this evening. If
> suitable, I plan to do as I did for the flyback transformer - build a
> pair of bobbins with a plexiglass pipe and lexan for the endcheeks
> (can be welded with methylene chloride (thanks Richard Hull and Kim
> Goins!). I have a small hand cranked winding machine available. I have
> wound a 22,000 turn transformer secondary to repair a demo unit here.
> However that took months and was tedious. I will use the lathe on
> slow speed and pile wind in all probability. I don't yet know what
> turns/Volt is. I certainly won't be using ultra small wire. Options
> are many at this stage.