Re: larger OR smaller than resonant ??? (fwd)

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: List moderator <mod1@xxxxxxxxxx>



---------- Forwarded message ----------
Date: Fri, 01 Jun 2007 19:21:23 -0700
From: Barton B. Anderson <bartb@xxxxxxxxxxxxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Subject: Re: larger  OR smaller than  resonant  ??? (fwd)

With an NST, you will be better off with LTR. See other post.
Take care,
Bart

Tesla list wrote:

>Original poster: List moderator <mod1@xxxxxxxxxx>
>
>
>
>---------- Forwarded message ----------
>Date: Fri, 1 Jun 2007 17:14:10 +0100
>From: James Howells <james@xxxxxxxxxxxxxxxxxxxxxxx>
>To: Tesla list <tesla@xxxxxxxxxx>
>Subject: Re: larger  OR smaller than  resonant  ???
>
>I am building my first NST tesla and have several options of Capacitors to 
>use however,
>But I have a dilemma I could do with some advice on
>
>The NST has a natural frequency of 18nF  and the capacitors I have will give 
>me either
>
>15-16 nF, 18nF or about  60 nF
>I have learned about 1.5 X Nat Frequency is best ( LTF) so I need about 27 
>nF
>
>But I can remember some discussion on Smaller than  resonant frequency also 
>being acceptable ... should I go for the 15nF combination ?
>
>
>( the spec on the NST is a little strange ... 3000 E 3000
>37 /52mA    127 W )
>
>
>
>
>
>Protected by www.SpamJab.com {UgzndUInruKjv2Cy9r}
>
>
>
>----- Original Message ----- 
>From: "Tesla list" <tesla@xxxxxxxxxx>
>To: <tesla@xxxxxxxxxx>
>Sent: Friday, June 01, 2007 4:43 PM
>Subject: RE: larger than resonant (fwd)
>
>
>  
>
>>Original poster: List moderator <mod1@xxxxxxxxxx>
>>
>>
>>
>>---------- Forwarded message ----------
>>Date: Fri, 1 Jun 2007 10:55:09 -0400
>>From: "Lau, Gary" <Gary.Lau@xxxxxx>
>>To: Tesla list <tesla@xxxxxxxxxx>
>>Subject: RE: larger than resonant (fwd)
>>
>>There are actually two reasons to use an LTR cap over a mains-resonant
>>cap.
>>
>>The most frequently cited reason is that should you open your static gap
>>too wide, a mains-resonant cap will resonate at 60 Hz with the NST
>>secondary and "ring_up", to whatever breakdown voltage your gap is set
>>to.  If your gap is set to break down at 50kV, it will get there, unless
>>your NST or your cap break down and smoke first :-(
>>
>>Using an LTR cap shifts the NST/cap resonant frequency away from the
>>mains-frequency, although it will still see some resonant-rise at 60 Hz.
>>If it did not, your gap would never fire if the variac was less than
>>100%.
>>
>>A less often acknowledged reason to use LTR is that maximum streamer
>>length correlates to bang size - 1/2 * C * Vgap.  With the same gap
>>breakdown voltage (cap charging or bang voltage), a larger capacitance
>>will yield a larger bang and result in a longer streamer, even if the
>>BPS rate is less.  Of course the lower BPS rate will make for a less
>>white-hot and impressive streamer - it's your choice.
>>
>>Regards, Gary Lau
>>MA, USA
>>
>>    
>>
>>>Date: Fri, 01 Jun 2007 05:54:39 -0400
>>>From: Scott Bogard <teslas-intern@xxxxxxxxxxx>
>>>To: tesla@xxxxxxxxxx
>>>Subject: larger than resonant
>>>
>>>Hey everybody,
>>>     Can somebody explain to me the advantage to using a "resonant" or
>>>"larger than resonant" tank capacitance?  I seen coils get huge sparks
>>>      
>>>
>>using
>>    
>>
>>>LTR and also very small tank capacitors, so what is the point?
>>>      
>>>
>>Thanks.
>>    
>>
>>>Scott Bogard.
>>>      
>>>
>>
>>
>>    
>>
>
>
>
>
>
>
>
>  
>