Re: Re[2]: MONSTER 100kW VTTC - Building now!

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

Original poster: "James" <mustang3-at-cox-dot-net> 

Hi John, List
     The VTTC doesn't seem to need the toroid. All I have ever noticed when
using one is you have to retune. Spark length is unchanged. The toroid does
look cool however so I use it. I haven't tried the small toroids on the
horizontal toob coil yet. I think the small toroids will look very good
there. However, I'll have to retune it for sure.
      Ok, as to corona coming off the top turn. I was able to control the
corona with a layer of insulation. I use a THICK(multiple coats) coat of
GOOP on the last inch. This stuff is the Tesla coiler's best friend. Had
that not fixed it, then I would have gone to a corona ring.
     The VTTC's are not too hard to tune, but they are "fiddely", just about
everything affects the spark length. The tickler coil(grid coil) needs to
turn the tube(s) hard off. Yet, you don't want to burn off excessive amounts
of power. Tuning the grid coil(amount of turns, position) and the grid leak
network will pay off in a longer spark. I use my o'scope and a high voltage
probe to observe the grid, sometimes odd spikes and things will appear. A
variac on the high voltage PS is also very handy for tuning. The voltage is
very high on the tube's anode, so I seldom look at it with the o'scope. My
coils run about -3000 volts on the grid when running at full power. The grid
leak resistor is 200-300W wirewound. Hot, hot, hot.

Later,

James
P.S. keep us posted on the VTTC work.

----- Original Message ----- dsFrom: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Monday, February 23, 2004 9:50 PM
Subject: Re: Re[2]: MONSTER 100kW VTTC - Building now!


 > Original poster: FutureT-at-aol-dot-com
 >
 > In a message dated 2/23/04 8:16:39 PM Eastern Standard Time,
 > tesla-at-pupman-dot-com writes:
 >
 > James,
 >
 > Nice results !
 >
 > I have one 5868 tube, but I haven't tried it yet except at
 > very low power.  Seems to be a good type of tube what what you've
 > described.  Did you find that you needed a toroid or corona ring
 > for over a 29" spark to prevent sparks from flaring off to the side from
 > the top turn of the secondary?  Do you find that the toroid helps your
 > spark length compared to operation without the toroid?
 >
 > Cheers,
 > John
 >
Some snipage
 >
 >