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Blown tranformer

Original poster: jdwarshui@xxxxxxxxx

You can make an  r.f. filter by winding two inches of 28 gauge on a
toilet paper core. Place this in series with a generic ignition
ballast resistors ( used on older cars ) Place on each 15k output.

A safety gap can be a simple L bracket from each 15k output to the
case or to a ground. Don't open this gap any more then you absolutely
need to (less then 1/2 inch) If your coil is out of tune they will go
off like mad (which is good!).

If you have a tar filled N.S.T remove the side and top tin, dig away
at the tar near the insulators until you find metal clip on the inside
of the tin, remove these. Now you can remove the insulators and the
end tins.

There will be two sets of secondary windings about an inch or so from
the ends of the case, you must locate these as they are easily damaged.

You want to fracture the tar without destroying wire. This takes a few
hours with a hammer. Avoid prying, use your fingers to pull out the

Solvents like kerosene will loosen the rest of the tar.
(soak overnight)

Get at the bolts, yank them out with vise grips then give the plates a
mighty whack on the ends. The plates will now separate, remove shims,
remove both secondary and primary.

Tag orientation of parts, draw a picture.

Now examine the secondary winding, look for burnt paper on the sides,
sometimes near the shims at the bottom.

If the paper is not to horribly burnt simple cleaning can often remove
enough tar and paper carbon so that the secondary will start working
again. You will know when the Ohm reading is nearly the same for both
secondary. (save the working secondary in any case!)

 If you break some of the fine secondary wire near the surface don't
sweat it, simply remove some paper and find some fresh wire. Looks to
be about a volt per turn, what's a few volts out of 15,000 ?

Of course you will need to run these N.S.T. in a bucket filled with
transformer oil. Have the oil circulate completely around the N.S.T.
You can use ordinary dime store mineral oil if transformer oil is
difficult to obtain. ( a little bit of vitamin E is not going to hurt

The N.S.T is much better off sitting in a tank of oil, you have not
wasted your time..

Good luck from Jared