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Re: Solid State article on website

Hi Terry and all,

He may have a grip on the coupling equation but as you noted he treated the
coil as a lump :) hope for me yet. This made it relatively simple to add the
coupling from the primary.

But note that the transmission line equations work with any C, L or any load
but I will say there h*** to work with complex refection coefficients and no
easy way to extract f.

I also noted his detailed form for k similar to a magnify.

Regards Bob

  -----Original Message-----
From: Tesla List <tesla-at-pupman-dot-com>
To: tesla-at-pupman-dot-com <tesla-at-pupman-dot-com>
Date: Friday, May 26, 2000 12:44 AM
Subject: Re: Solid State article on website


>Original Poster: Terry Fritz <twftesla-at-uswest-dot-net>
>
>Hi Malcolm,
>
>At 04:56 PM 5/24/00 +1200, you wrote:
>>Hi Terry, all,
>>                    I have a number of comments to make on the paper
>>referred to. I conducted expts using a bank of MOSFETS in place of
>>the gap a few years ago using a 30V DC supply and wound up
>>producing 1/2" sparks under some conditions.
>>
>>On 23 May 00, at 18:30, Tesla List wrote:
>>
>>> Original Poster: Terry Fritz <twftesla-at-uswest-dot-net>
>>>
>>> Hi Bob,
>>>
>>> WOW!!!!  This paper is a pure treasure!!!  Very highly recomended to
all!!
>>>  The paper at:
>>>
>>> http://www.stellarproducts-dot-com/synch.htm
>>>
>>> Also has significance to us doing other Tesla coil secondary behaviour
>>> stuff (the "Malcolm's Ruler" model) we haven't told you all about yet
;-)))
>>>
>>> I do not know this Dr. Bruns but he seems like a very interesting person
>>> who is very knowledgeable in these areas I like so much!  :-))
>>>
>>> Cheers,
>>>
>>> Terry
>>
>>Points I would like to note:
>>
>>(1) He says that Cself was inferred from measuring the frequency
>>but I didn't see the formula he used. Presumably it was the classic
>>lumped resonance formula. Anyone see it there? It would appear
>>that he was measuring Medhurst's value for Cself.
>
>He apparently had a large value fixed cap on the end of the secondary that
>overwhelmed the coil's own self (Medhurst) capacitance.  Just the end
>capacitance and the coil's inductance should have given a number close to
>the resonant frequency allowing the coil's self C to be neglected.
>
>>(2) He connected a comparatively huge lump of C across his
>>secondary to bring Fr down. Anyone see something wrong with
>>doing that (if this is supposed to be indicative of a normal TC
>>configuration)? Maybe not.
>
>It may have a bad effect on a transmission line model but should not make
>much theoretical difference in a pure lumped model.  I imagine he simply
>did what he had to do to get the thing to work ;-))
>
>>(3) There was an indication in one of the oscillographs that his gap
>>quench was less than perfect on at least some occasions. It showed
>>up as a residual beat in the primary waveform and a matching dip in
>>the secondary ringdown envelope.
>
>His fancy FET switch could quench whenever he wished.  I notice in one
>graph he turns the gap off in the middle of the second ring up and has his
>computer model do the same.  Perhaps he was searching for the coherence
>voltage rise predicted in the Corum's old paper ;-))  It is also
>interesting to note the very low voltages he was working with.  I imagine
>he had relatively perfect control of his given setup.
>
>Cheers,
>
> Terry
>
>
>>
>>I'd be interested to hear other's comments on the paper.
>>
>>Regards,
>>Malcolm
>>
>
>
>