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Re: Towards the autonomous lifter - electrostatic voltage generators.

Original poster: Terry Fritz <teslalist@xxxxxxxxxxxxxxxxxxxxxxx>

Hi Chris,

At 04:28 PM 7/3/2005, you wrote:
If you're making a low power circuit then couldn't you use really thin wire?

Yes ;-) There are even ways to glue the wire to itself as well so the coil does not even have a supporting form!!

Also doesn't a lifter need DC to provide a constant E field that causes the ions to move?

That is a DEEP question!! If the output needs to be rectified, then rectifier diodes may be needed. However, that makes it so energy from the output structure cannot return to the coil which may cause serious detuning at the detriment of the coil's resonance. The diode junctions themselves also have a significant capacitance which may also foul the resonance.

We will have to learn from our lifter expert if AC is acceptable for the power supply. If not, we have more problems :O

What is the effect of a RF lifter and has anyone managed to power a lifter off a big TC using some thin transformer wire? Is there anyway of rectifying the output of the TC i.e. a single HV low power diode? Or maybe a more unconventional method using standing waves so the lifter only ever sees voltage peeks. 

Significant questions.....

Are we 100% sure that the BB effect is pusdo science, even at RF HV? I was thinking that the momentum of electrons at high velocity (relativistic mass) would be enough to make a lifter 'jump' with each HV cycle (probably dreaming again).

We'll leave the "great science questions" to our lifter friends... We're tired of that right now...


You can get surface mount 555s and components that will be very light.

They make 555 packages that are the size of a pinhead... I think it is called "Micro SMD". But it might be out of reach for those without some pretty good mounting equipment.

http://www.national.com/an/AN/AN-1112.pdf

I'd imagine given the low inductance and capacitances it would be very hard to tune unless you some how decoupled from the capacitance caused by the lifter, or would the lifter become the 'top load'.

Somehow, the lifter load must be a very significant part of the topload. I hope we don't have to worry about "active" tuning too!!!

Night vision goggles use small light power supplies for the photo multiplier tubes. But I don't think they have nearly enough current. Lifters not only need high voltage, but they need it at some significant delivered power levels too!

Cheers,

        Terry



Thanks

Chris

----- Original Message ----- From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Sunday, July 03, 2005 8:39 PM
Subject: Re: Towards the autonomous lifter - electrostatic voltage generators.


Original poster: Terry Fritz <teslalist@xxxxxxxxxxxxxxxxxxxxxxx>

Hi Bob,

At 08:09 PM 7/1/2005, you wrote: 
.....................

I wanted to save weight by eliminating the
transformer. But it may turn out the large number of
components for a kilovolt CW multiplier without
transformer would cancel out the weight savings. I
discussed this in a post to www.powerlabs.org copied
below. A question I would like to see answered is what
is the weight for a microfarad capacitor?
The post refers to the 555 oscillator IC. I needed
that because the CW requires AC while the lithium
batteries put out DC. The 555 provides a simple
lightweight method for converting DC to AC:

DC to AC Inverter with the 555.
http://www.uoguelph.ca/~antoon/circ/555dcac.html


Bob Clark 
.................

I ran about 1 million models through ScanTesla to see what it would come up with for a Tesla coil powered lifter. I assumed a 40V input and a DRSSTC drive system. It was driving 50M ohms or 50kV at 1mA @ 50W.

ScanTesla  V-7.40  July 1, 2005  Terry Fritz
Cprimary = 1.000000e-008
Lprimary = 2.105100e-004
Rprimary = 1.500000e-001
Coupling = 0.350000
Csecondary = 0.200000e-010
Lsecondary = 9.000000e-002
Rsecondary = 3.910000e+002
Cload = 1.000000e-007
Rload = 5.000000e+007
BPS = 1000.000000
Dwell (T1) Time = 5.000000e-004
Ilprimay Maximum = 24.595672
ICprimary RMS = 8.769052
VCprimary Maximum = 3883.999639
VCsecondary Maximum = -73522.366980
Coil Power = 64.282184   Primary Bang Energy = 0.064282
Load Power = 13.118890   Load Bang Energy = 0.013119
Primary F0 = 109694.225469   Secondary F0 = 118627.090570

It actually does not look too bad but the pulse output graph shows a new complication:

http://hot-streamer.com/temp/LifterPower-01.gif

Basically, it would need to be "voltage regulated". You would need a pretty good coil but you could not run it full power or the voltage would go far too high. If you made it for a lower voltage, it would have no efficiency... So you would need to have a feed back path for the output voltage and modulate the DRSSTC circuit to maintain say 50kV on the output. So we have:

1. Vacuum impregnated epoxy "Tesla coil" to get high voltage in a small light size.
2. DRSSTC drive from say a standard little H-bridge DC motor driver.
3. Primary current feedback.
4. Output voltage feedback and regulation.

A 10nF 4000V RF cap is something American Technical Ceramics could come up with.

The RMS current though the driver "might" be a problem!! Most small drive ICs would need external FETs to drive that kind of RMS current. But the current should go down in a more steady state situation.

It is probably "possible" to make a little Tesla coil air core HV power supply like this. But it is not at all straight forward to do. Probably be some "bleeding edge" problems to be worked out...

I wonder if the epoxy coil would end up weighing just as much as a small standard ferrite...

Use aluminum magnet wire to save weight on lower current stuff. DigiKey also has 0.032 inch double sided PCB material which is far lighter there too...

I trust you have looked into those 12v mini inverters for lasers like Meredith Instruments sells too:

http://www.mi-lasers.com/cgi-bin/shopper.cgi?search=action&keywords=power_supply

They look heavy, but you might be able to get the bare guts before they are impregnated with plastic and have the voltage changed if you were real nice to whoever makes them OEM... That would save a ton of work!

Cheers,

        Terry