Re: NST Rebuild

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Steve Zeitler" <zeitler@xxxxxxxxxxx>


----- Original Message ----- From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Wednesday, May 18, 2005 3:55 PM
Subject: NST Rebuild


> Original poster: JBarrett@xxxxxxxxxxxxxxxx
>
> Has anyone ever rewound a NST secondary or can new pre-wound secondaries 
> be purchased?  I would like to build a good HV transformer. I have several 
> large cores from some old equipment that was scrapped at an airport. Some 
> of it is 3 phrase.
>
> Thanks
> Jim
> I built 2 HV transformers a while back. The time consuming part was 
> winding the secondaries.
As I recall, 9000 turns per, 150T a layer, 60 layers #30 wire, with a layer 
of 2"wide Kapton tape between layers.
Each one took about 40 hrs. I was living alone at the time so I set up the 
winder in the living room so I could
watch TV at the same time. Oh yeah, add a case of beer to the cost of each 
xfmr.
The Primaries were 120T #14 wire giving an unballasted output of 9kv +/- 
each. With 4ohm resistive ballasting (each) I
got 6kv each for 12kv total @ 200 ma +/-. They run dry...no oil. The coil 
no longer exists but the trannies do, I still have them, awaiting another 
coil project.

   Steve Z.....