Re: Damaged / Destroyed NST?

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "sundog by way of Terry Fritz <twftesla-at-uswest-dot-net>" <sundog-at-timeship-dot-net>

Ouch!  Don't fire up the NST across the gap without the caps hooked
up.  I lost one that way. :(

An NST is easy to tell if it's good or not.  If you can draw about
the same size arc off each side, each starting about the same
distance from the case, and the current draw on the primary agrees
with the calculated draw when the secondarys are shorted to ground,
it's good.  NST's are simple beasts.

  Start Simple.  run just the simple coil with a breakout and no
NST protection.  If you get output, change 1 thing at a time till
your output falls off/dissapears.  if it's the protection circuit,
I'd triple-check each part to make sure it's not the problem,
and/or disconnect/bypass each part to find the problem.  Your coil
sounds good.  Run a narrow gap and test away
                                                        Shad
-----Original Message-----
From: Tesla list <tesla-at-pupman-dot-com>
To: tesla-at-pupman-dot-com <tesla-at-pupman-dot-com>
Date: Monday, January 15, 2001 9:15 PM
Subject: Damaged / Destroyed NST?


>Original poster: "Simon Yorkston by way of Terry Fritz
<twftesla-at-uswest-dot-net>" <quantumx-at-ozemail-dot-com.au>
>
>After sending the following message, i was wondering - could these
be the
>symptoms of a busted NST? Just wondering. There is no smoke /
smell /
>anything unusual out of the tranny when running tho..
>
>------------------------------------------------------------------
----------
>-------------------------------------------------
>
>Hi all.
>After extensive work, I fired up my Tesla coil. I got absolutley
nothing, no
>matter where I tapped it, or if I had a large or small toroid on
top.
>
>As some as you may remember, prior problems of metal-cased
resistors [as per
>Terry's NST protection scheme] prevented me tapping my 12 terminal
SSPG
>[Static Gap] past 4 or 5 terminals. I purchased, on the advice of
another
>coiler, a few cermaic resistors, and made a MMR. I also remade my
safety
>gap.
>
>When I powered up [w/o topload or tank caps] something strange
happened. On
>the safety gap, there was a continuous very "smooth" arc [eg, not
the loud
>usual "cracks"] jumping across the LARGER safety gap. WTF? I can
only assume
>that the other 'side' of the protection scheme is faulty- good
assumption?
>[[What's strange is that the resistors on both sides were warm, so
the power
>was getting through]]
>
>I retapped the Sparkgap to just 2 gaps, and powered up. This moved
the
>sparks into the sparkgap, with the safety arcing every 5 seconds
or so.
>Strangely, the SSPG would suddenly stop firing, and the spark
would go the
>safety. I though it might be ionised air, but I have a fan on top
of the
>SSPG.
>
>Anyway, I seemed to fix it, and placed on the topload. The SSPG
made those
>louder 'smack' sounds that we seem to be used to, but I got
NOTHING from the
>topload, despite any taps on the primary. *sigh*
>
>Notes>
>> There was no unusual sparks in unexpected places [except for
when the tank
>arced to the ground [proves the tank was ok]]
>
>
>I must say, this coil is beginning to annoy me; it's schematically
and
>physically [as far as i can see] and electrically correct, but I
am getting
>VERY poor / none at all results. It seems to be at the moment a
very costly
>peice of wires :)
>
>Thanks, any ideas / support / tissues would be appriciated.
>Simon Yorkston
>
>
>
>
>