Re: Problems with First Tesla Coil

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

Original poster: "D.C. Cox by way of Terry Fritz <twftesla-at-qwest-dot-net>" <resonance-at-jvlnet-dot-com>


Run the "scrap wire" primary test with 30 turns of #12 AWG clipped on some
cardboard with slits and you will solve the tuning problem without blowing
your caps up.

Also run a sharp point off the toroid for initial tuning procedures.

Dr. Resonance




----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Monday, August 26, 2002 8:37 PM
Subject: Problems with First Tesla Coil


> Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<dhmccauley-at-spacecatlighting-dot-com>
>
> Hello,
>
> I am having some problems with my first conventional tesla coil.  I've
been
> trying to tune the thing all night, but no success.  Only a few blown MMC
> capacitors.  Here are my specifications:
>
>
> 15kV/60mA NST
> Synchronous Rotary Spark Gap 120BPS  (with safety gap)
> .0275uF, 28kV MMC (LTR type)
> 13 Turn Primary
>
> Here are my questions - hope their not too many . . .
>
> 1.  From my calculations, if I was using a 0.0106uF capacitor, my primary
> wouldn't be able to tune this as it calculates to about the 15 turn. (Mine
> is only 13 turns)  However, if I make this calculation
> with my LTR capacitor (.0275uF), then the primary should be tapped
> approximately 7-8 turns.  Does this sound right, or when using a LTR sized
> cap with a SRSG do I need to do something else in my calculations???
>
> 2.  I've never tuned a tesla coil before.  Tonite I was just going around
to
> every turn, inching up my variac to about 25%, and monitoring current or
> hoping to see a little streamer or something.  But nothing.  For a typical
> primary this size, how much tapping range is there to actually have the
> think work a little.  Is it very narrow, or if i'm within a half a turn
i'll
> get some output???
>
> 3.  When I actually do hit resonance, at what percentage output voltage
> should i expect to see some type of streamers begin???
>
> 4.  Can the quality of the RF ground be the difference between output and
no
> output???  I know some people on this list claim to get output even when
the
> RF ground is left floating??
>
> 5.  Anything else that i might be missing???  The SRSG is running fine and
> sounds like its properly running.  It is synchronized with the 60Hz and
> tuned correctly.
>
> Tomorrow I will use a smaller toroid to see if I indeed have a primary
with
> too few turns.
>
> Thanks for all the help.  I'm about scratching my head right now.
>
> Dan
>
>
>
>