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RE: Building A VTTC



Original poster: "Henry Hurrass" <Dr.Hankenstein@xxxxxxxxxxxxx>

No problem, Cameron.

I understand what you are trying to accomplish and I agree by all means
that the only way get there is by doing the actual experiment; as Nikola
Tesla once said: "The work is not complete until the experiment has been
done."

Your recent work has put the "Armchair Coiler's Group" to shame! Keep up
the good work!

Cheers,
Dr.Hankenstein


> [Original Message]
> From: Tesla list <tesla@xxxxxxxxxx>
> To: <tesla@xxxxxxxxxx>
> Date: 8/23/2006 12:15:52 PM
> Subject: RE: Building A VTTC
>
> Original poster: "Cameron B. Prince" <cplists@xxxxxxxxxx>
>
> Hi Henry,
>
> Thanks for your comments and I wholeheartedly agree... However, I think
you
> guys are somewhat missing the reason I suggested the counter display. In
my
> tuning one thing that has consistently been a difficulty is reproducing
the
> same environment with different components. Having a display would allow
me
> to know that I am back to a certain point I was before or allow me to
> document where I am currently with a particular result. It's a metric.
>
> I am using my senses now and tick marks around the knobs, but those only
go
> so far. I have an isolation transformer and HV probe on the way so I can
do
> some measurements with the scope, but having a display built-in to the
panel
> would be ideal. Let's not fail to consider the coolness factor too. :)
>
> Dave Sharpe has been helping me some already and I'm going to start by
> building the updated controller circuit he helped Dan design at:
> http://www.easternvoltageresearch.com
>
> Once I have it going I plan to try and integrate the counter display. It's
> only a small number of components and shouldn't be a big deal to build on
a
> breadboard.
>
> Thanks again for you comments,
>
> Cameron
>
>
>
>  > -----Original Message-----
>  > From: Tesla list [mailto:tesla@xxxxxxxxxx]
>  > Sent: Wednesday, August 23, 2006 7:51 AM
>  > To: tesla@xxxxxxxxxx
>  > Subject: Re: Building A VTTC
>  >
>  > Original poster: "Henry Hurrass" <Dr.Hankenstein@xxxxxxxxxxxxx>
>  >
>  > I think the whole idea of the staccato controller in the first place
is to
>  > limit the "watts dissipation" that the plate really thinks it's
seeing. As
>  > an example, if you limit the duty cycle to say 50%, you could
conceivably
>  > double the plate dissipation (thus producing a longer spark), but the
>  > "average plate dissipation" would still be below the "max plate
>  > dissipation" allowed for the tube. I.E.: 500W times 50% duty cycle
equals
>  > 250W avg. = longer spark. Without the staccato controller (which is
really
>  > only a pulse width or duty cycle controller AKA: CW Mode) the plate
would
>  > normally melt. I personally do not like to see plates glowing any color
>  > other than black for longevity of the tube. Who cares what the BBS
rate is
>  > as long as you find the sweet spot where you would back-off the duty
cycle
>  > to make your coil a long time AND a long spark performer. Look at the
>  > plate: If it's glowing, you are probably giving too much "hammer".
enjoy
>  > and BTW nice work!
>  >
>  > regards,
>  > Dr. Hankenstein
>  >
>  >
>  >  > [Original Message]
>  >  > From: Tesla list <tesla@xxxxxxxxxx>
>  >  > To: <tesla@xxxxxxxxxx>
>  >  > Date: 8/22/2006 11:39:31 AM
>  >  > Subject: Re: Building A VTTC
>  >  >
>  >  > Original poster: "Steve Ward" <steve.ward@xxxxxxxxx>
>  >  >
>  >  > Since the pulse rate is always some even division of 60, its pretty
>  >  > easy to listen to hear the 30, 20, 15, and 10pps.  Below that you
may
>  >  > need a counter.  Most people have scopes or maybe a meter that can
>  >  > count, i dont think i would bother putting a counter circuit into
the
>  >  > staccato controller.
>  >  >
>  >  > Steve
>  >  >
>  >  > On 8/21/06, Tesla list <tesla@xxxxxxxxxx> wrote:
>  >  > >Original poster: "Cameron B. Prince" <cplists@xxxxxxxxxx>
>  >  > >
>  >  > >
>  >  > >Hey guys,
>  >  > >
>  >  > >I think the consensus is we need some sort of counter to help
>  > determine
>  > the
>  >  > >current pulse rate of the staccato controller. John, this is what I
>  > had
>  >  > >emailed you about a few weeks ago. I think it would be really nice
to
>  >  > >incorporate two 7 segment displays into the controller that display
>  > current
>  >  > >pulses per second. I have briefly looked into this and found the
>  > schematic
>  >  > >here:
>  >  > >
>  >  > >http://martybugs.net/electronics/speedo.cgi
>  >  > >
>  >  > >It's for a digital speedometer display but I think the concept is
>  > about
>  > the
>  >  > >same:
>  >  > >
>  >  > >1) Take a sample
>  >  > >2) Perform an average
>  >  > >3) Display value
>  >  > >4) Return to step 1
>  >  > >
>  >  > >What are your thoughts on this circuit and adapting it to interface
>  > with
>  > the
>  >  > >staccato controller? Is there a less complex way or circuit that
would
>  >  > >provide the same results that you know of?
>  >  > >
>  >  > >Thanks,
>  >  > >Cameron
>  >  > >
>  >  > >  > -----Original Message-----
>  >  > >  > From: Tesla list [mailto:tesla@xxxxxxxxxx]
>  >  > >  > Sent: Monday, August 21, 2006 6:58 PM
>  >  > >  > To: tesla@xxxxxxxxxx
>  >  > >  > Subject: Re: Building A VTTC
>  >  > >  >
>  >  > >  > Original poster: FutureT@xxxxxxx
>  >  > >  >
>  >  > >  > In a message dated 8/21/06 4:07:27 PM Eastern Daylight Time,
>  >  > >  > tesla@xxxxxxxxxx writes:
>  >  > >  >
>  >  > >  > >It seems that you have made a quantum leap in
>  >  > >  > >the stacatto controlled VTTC that probably hasn't been pa-
>  >  > >  > >ralleled since the 1990s when John Freau himself first intro-
>  >  > >  > >duced the stacatto controlled VTTC, capitalizing upon the
>  >  > >  > >higher output from the same power input through the
>  >  > >  > >priciple of lower duty cycle firing. And I also think that it
>  >  > >  > >should be pointed out to the rest of the list that this is
your
>  >  > >  > >very first VTTC project, so basically you've made these
>  >  > >  > >advances as a VTTC beginner!
>  >  > >  > >
>  >  > >  > >Keep up the good work,
>  >  > >  > >David
>  >  > >  >
>  >  > >  >
>  >  > >  > Cameron, David,
>  >  > >  >
>  >  > >  > Yes, Cameron has obtained very impressive results from his
>  >  > >  > VTTC project.
>  >  > >  >
>  >  > >  > My original coil that gave the 36" sparks, and later
>  >  > >  > the one that gave 38" sparks didn't have a staccato system
>  >  > >  > attached, so they ran at 60 PPS, and drew a lot of power.
>  >  > >  > These early designs were unable to give the straight sword-like
>  >  > >  > sparks, so the sparks tended to get a lot shorter when the
>  >  > >  > staccato feature was added.  I did at some point add the
>  >  > >  > staccato feature but the sparks got shorter when the staccato
>  >  > >  > was operating.
>  >  > >  >
>  >  > >  > One of my early coils gave the sword-like sparks.  In this
>  >  > >  > coil the spark length did not decrease in the staccato mode.
>  >  > >  > I could reduce the pulse rate to 1 pulse per minute, and the
>  >  > >  > sparks remained just as long.  But this was a smaller coil
>  >  > >  > which produced 20" sparks from a single 4-250A tube
>  >  > >  >
>  >  > >  > When I added the staccato system to my coils in general
>  >  > >  > I didn't go back to modify the coils to take advantage of the
>  >  > >  > staccato features, so the sparks didn't get any longer, the
>  >  > >  > input power simply decreased.
>  >  > >  >
>  >  > >  > When I had spoken to
>  >  > >  > Steve Ward and others, I suggested that they modify their coils
>  >  > >  > (compared to mine) by lowering the plate impedance to take
>  >  > >  > advantage of the staccato capabilities.  This is what I was
>  > planning
>  >  > >  > to do but I got involved in other work.  Also around that time
I
>  > had
>  >  > >  > introduced the zero-crossing staccato circuit which helped a
lot
>  > for
>  >  > >  > staccato stability.  I sent this schematic to Steve Ward and he
>  >  > >  > incorporated it into his coil and placed the schematic at his
>  >  > >  > website.  He did optimize his coils to take advantage of the
>  >  > >  > staccato, by lowering the plate impedance.  Cameron has
>  >  > >  > done that also.
>  >  > >  >
>  >  > >  > Some later coils that I built did give the sword-like
>  >  > >  > sparks, so they were able to maintain their spark lengths
>  >  > >  > while running at a slower staccato pulse rate.  One later
design
>  >  > >  > coil (circa Feb, 2001) produced 24" swordlike sparks in the
>  >  > >  > staccato mode and also without staccato.  This coil used two
>  >  > >  > 833A tubes and was capable of running without staccato
>  >  > >  > without overheating the tubes.  It produced 24" sparks.
>  >  > >  > When running without staccato it drew 2400 watts while
>  >  > >  > producing the 24" sparks.  By using the staccato, the
>  >  > >  > power draw could be dramatically reduced depending
>  >  > >  > on the pulse rate.  For example if the coil was run at 30 PPS,
>  >  > >  > Then it drew 1200 watts (somewhere around 10amps).  If the
>  >  > >  > coil was run at 15 PPS, then it drew 600 watts (~ 5 amps).
>  >  > >  >
>  >  > >  > I use a similar formula to my formula for spark gap coils,
>  >  > >  > for VTTC's without staccato.
>  >  > >  >
>  >  > >  >       spark length inches = 0.5*sqrt input watts.
>  >  > >  >
>  >  > >  > This formula is for VTTC's which are running at the full 60 PPS
>  >  > >  > (no staccato).  The coils will of course be much more
"efficient"
>  >  > >  > in staccato mode.
>  >  > >  >
>  >  > >  > As an example there is my 2nd large VTTC coil which gave the
>  >  > >  > 36" sparks at around 5500 watts.  So if we take the sqrt of
>  >  > >  > 5500 = 74.16.  Then multiplying this by 0.5 gives 37" which is
>  >  > >  > very close to the 36" I obtained.  I think I turned up the
power
>  >  > >  > a little higher to get the 38" which I eventually obtained.
>  >  > >  >
>  >  > >  > Now we can do an example with staccato mode.  Consider
>  >  > >  > my coil that gave 24" sparks both in or out of staccato mode.
>  >  > >  >
>  >  > >  > without staccato:
>  >  > >  >
>  >  > >  >     24.49" spark length = 0.5*sqrt 2400 watts
>  >  > >  >
>  >  > >  > So it can be seen the formula is quite accurate for this coil
>  > also.
>  >  > >  >
>  >  > >  >    But with staccato at 20 PPS the formula must be modified.
>  >  > >  >
>  >  > >  >    24" spark length = 0.76*sqrt 1000 watts
>  >  > >  >
>  >  > >  > note I used 1000 watts instead of 800 watts to allow for the
>  >  > >  > filament power for the two tubes.  In some of the calcs here
>  >  > >  > I didn't bother accounting for filament power.
>  >  > >  >
>  >  > >  >    At 15 PPS:
>  >  > >  >
>  >  > >  >    24" spark length = 0.86*sqrt 800 watts
>  >  > >  >
>  >  > >  > I think at some particular slow pulse rate
>  >  > >  > the spark length diminished some.  I'm not sure though.
>  >  > >  > If the staccato pulse rate
>  >  > >  > is very slow, the spark will not appear continuous but will
>  >  > >  > appear pulsed when viewed by eye.  When speaking about
>  >  > >  > the efficiency of a staccato tube coil, it's best to give the
>  >  > >  > staccato pulse rate because the pulse rate has such a
>  >  > >  > dramatic effect on the power draw.  When the coil runs
>  >  > >  > at 30 PPS, the sparks look almost as full as at 60 PPS.
>  >  > >  > At 20 PPS the sparks look good too.  Each pulse rate
>  >  > >  > has it's own interesting appearance and sound.  When
>  >  > >  > the rate gets slow enough, down to 15 PPS or so, only
>  >  > >  > a single sword like spark will be seen.  This sword spark
>  >  > >  > will waver back and forth slightly as the coil runs.  This
>  >  > >  > type of spark can be seen at my website, as well as
>  >  > >  > other types of sparks.
>  >  > >  >
>  >  > >  > Basically if you optimize the VTTC for staccato, then it will
>  >  > >  > not be able to run continuously without staccato.  The tubes
>  >  > >  > will overheat.  So there's a tradeoff.  Either use a high plate
>  >  > >  > impedance and permit the coil to run at the full 60 PPS
>  >  > >  > (no staccato), and limit the spark length (even with staccato
>  >  > >  > turned on).   Or use a lower plate impedance and only
>  >  > >  > run in the staccato mode at 30 PPS or less to prevent the
>  >  > >  > tube from burning up.  But longer sparks will be obtained.
>  >  > >  > The coil can be turned up to full power without staccato
>  >  > >  > for short durations, but not continuously.  Keep an eye
>  >  > >  > on the tube plate and watch for excessive redness.  Turn
>  >  > >  > down the power very quickly as needed.
>  >  > >  >
>  >  > >  > John
>  >  > >  >
>  >  > >
>  >  > >
>  >  >
>  >  >
>