Re: Looking for plans/materials for a tube type coil and a question.

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

Original poster: "David Trimmell by way of Terry Fritz <twftesla-at-uswest-dot-net>" <davidt-at-pond-dot-net>

Hi, I can probibly help with some info. But first know that VTTC's are at
least as dangerous Pig or PT powered coils. See my web site at :
www.ChaoticUniverse-dot-com/ and follow links to tesla/tube coils. Here there
is a copy of a old post from John Freau for making a MOT powered 833A tube
coil producing 20 inch sparks:
 http://216.36.6.9/webdoc2.htg/Tube_coil/833Tube_coil.htm
The schematic shown here: http://216.36.6.9/webdoc2.htg/Level_Shifter.htm
shows the layout, but note that the component values are not
accurate. This design principle can work with a number of different tubes,
as 833, 304, etc., only plate voltage and grid bias need adjustment as per
tube specs.

As far as to your question regarding hight to diameter ratio of vac. coil
secondaries, you got me? Perhaps due to the low(er) voltage the "candle
stick" secondaries have not died off like they have with disruptive
coils? I use secondaries 4/1, 4.5/1, but greater ratios should also work
fine for small tube coils. Frequency is not the crucial factor, but I
prefer to work below 500KHz.

Other good web sites and info can be found here:
http://users.better-dot-org/roverstreet/projects/tube_coil/tube.htm
http://hometown.aol-dot-com/futuret/page2.html

Hamfests and ebay are the best places to find tube coil stuff.

Regards,

David Trimmell

 On Thu, 22 Feb 2001, Tesla list wrote:

> Original poster: "Garry Freemyer by way of Terry Fritz
<twftesla-at-uswest-dot-net>" <garry-at-ndfc-dot-com>
> 
> I have one set of plans, that uses two 805s in parallel and it says it will
> put out ~6".
> 
> I am looking to build a tube type coil that would put out a little more than
> that. Between 8" to 12" and would like to get some url's or plans for such a
> coil as well as maybe names of companies to buy the plastic for the
> secondary and primary.
> 
> I would be interested in buying componants for it. As I will be using my tax
> refund that I'll get back six to 8 weeks from now (about $700), I would like
> to pay fair compensation for any materials I buy. I have about $10 extra
> taken out of my weekly paycheck towards taxes so that is what most of the
> refund is. I won't be in a particular hurry to get this up and running. I
> wish to take my time and build something that looks good as well as works
> well. If I start with the attitude and expectation that I may be four to six
> months from the time I start building it, I will hopefully be more patient
> with building it and not be so easily frustrated by delays and setbacks. My
> idea is to have this finished about September at the earliest.
> 
> One thing I have been a little puzzled about is that the tube type
> secondaries seem to follow a 10:1 ratio while the spark gap driven ones seem
> to be more like 5:1 or 4:1 ratio. I am wondering what the reason for this
> is?
> 
> Is it because it runs at a higher frequency?
> 
> Might a tube type coil of 5:1 ratio work better than one of 10:1?
> 
> 
> 
>