Re: 8Kva Quad 833C VTTC
Duncan, Thu Feb 15 2007, 05:31AM

Holy cra... that is huge Can't wait to see some photos/videos of it going! Is there going to be any blue lighting in the frame of this one?

Re: 8Kva Quad 833C VTTC
ragnar, Thu Feb 15 2007, 12:08PM

Your work with your plastics, Chris, is beautiful... absolutely beautiful, every time. =)

Re: 8Kva Quad 833C VTTC
Electroholic, Thu Feb 15 2007, 02:11PM

DRVTTC? Full bridge of 833C?

Re: 8Kva Quad 833C VTTC
Jrz126, Thu Feb 15 2007, 03:11PM

wow, that coil looks great.
I wish I could keep my garage/work area that clean

Re: 8Kva Quad 833C VTTC
J. Aaron Holmes, Thu Feb 15 2007, 04:21PM

Sweet! I think the likelihood of competing with Chris in plastics seems pretty small. Somebody will have to strike out in their own direction and create a retro all-metal VTTC that looks like a combination between a Heathkit linear amp and a 1957 Chevy, complete with chrome accents Then we'll have both ends of the spectrum covered in style.

As for my own present VTTC endeavor, I was planning on using some wooden chopping blocks for the base, similar to what Duncan is doing for his small SGTC in the Projects section. Looks pretty nice. I don't trust myself to work with plastic; it just always ends up a mess Maybe someday I'll gather the courage to play with plastics some more...

Chris: Once you get the filaments all wired, you'll have to post a picture of your 833Cs glowing in unison! Should be almost as cool-looking as the sparks! Almost.

Regards,
Aaron

Re: 8Kva Quad 833C VTTC
Dr. Drone, Thu Feb 15 2007, 11:21PM

Re: 8Kva Quad 833C VTTC
Boost, Fri Feb 16 2007, 03:09PM

MOT's are suxx for 4 833C's.
Try to use real plate xfrmr 8+kVA real power instead.

Re: 8Kva Quad 833C VTTC
ragnar, Fri Feb 16 2007, 03:22PM

Heheh, out of curiosity Chris, what's your day job? =P

Re: 8Kva Quad 833C VTTC
Steve Conner, Fri Feb 16 2007, 04:30PM


That may be so, but Chris Hooper seems to know what he's doing and has built several nice VTTCs in the past. I'm sure he can make it work fine with MOTs.

BTW, John Freau has made a VTTC with four 833As powered by a pole pig:

Re: 8Kva Quad 833C VTTC
J. Aaron Holmes, Fri Feb 16 2007, 05:25PM

I'm pretty sure Chris has a 14.4kV pig (saw a pig on his site once). Stick a 120V variac across the 240V lugs and you get a nice, big 0-7.2kV transformer. That would probably do great as a VTTC supply

But the "portability" aspect of the VTTC kind of disappears then. That, I think, is the attraction of the smaller transformer + doubler arrangements.

Regards,
Aaron, N7OE

Re: 8Kva Quad 833C VTTC
Dr. Drone, Fri Feb 16 2007, 05:49PM

Re: 8Kva Quad 833C VTTC
Dr. Drone, Mon Apr 09 2007, 01:56AM

Re: 8Kva Quad 833C VTTC
Part Scavenger, Mon Apr 09 2007, 02:40AM

HOLY SMOKES! Where was I in February?!! Talk about cool!

Re: 8Kva Quad 833C VTTC
Ken M., Mon Apr 09 2007, 04:04AM

CH_R I salute you and your artful skill with Plexy glass! Back on point...God thats gonna be a nice coil!

Re: 8Kva Quad 833C VTTC
Vaxian, Wed Apr 11 2007, 09:07AM

I watch with interest as I too build mostly with plastic (Lexan to be exact).
Mine don't look nearly as good but I'm working on my shop, sooner or later my coils will look at least good.

Lexan is very easy to work with and I get mine FREE

Keep us posted on this VTTC of Mamouth proportions!
Can't wait to see it fired up!

Keep em Glowing!

Dan

Re: 8Kva Quad 833C VTTC
Dr. Drone, Sun Apr 29 2007, 07:21AM

Re: 8Kva Quad 833C VTTC
Brett Miller, Mon Apr 30 2007, 12:46AM

Chris,

The rack of 833C's looks amazing, and I too love the look of LED's in your polycarbonate based coil structures. I'm sitting here now in between two PC's with red and blue LED case mods.

By the way, your 810 vttc looks very cool as well. I may have to build a single tube version of something like that sometime. Those Penta Labs tubes are hot.

-Brett

Re: 8Kva Quad 833C VTTC
Dr. Drone, Wed May 16 2007, 01:47AM

Re: 8Kva Quad 833C VTTC
Coronafix, Wed May 16 2007, 10:13AM

My God Chris!
That thing is going to be the monster of all VTTCs!
No wonder you need to wind a larger secondary.
Are you going a bigger toroid as well or do you think
the 12X3 is enough?

Re: 8Kva Quad 833C VTTC
Dr. Drone, Wed May 16 2007, 02:32PM

Re: 8Kva Quad 833C VTTC
Dr. Drone, Sun May 27 2007, 05:30AM

Re: 8Kva Quad 833C VTTC
Myke, Sun May 27 2007, 07:11AM

Very cool looking. How do you keep your workshop so clean?

Re: 8Kva Quad 833C VTTC
Steve Conner, Sun May 27 2007, 10:34AM

Yay, looks awesome!

Re: 8Kva Quad 833C VTTC
Marko, Sun May 27 2007, 12:25PM

Holy ***p chris. Tell me, how do you cut up all tha plexy? CO2 laser station?

Even with laser I noticed that it starts to run 'out of focus' for thicker plastics and makes edges skew.

Recently I was trying to make two simple 20*20cm squares out of some thicker plexi and I messed up by several mm.

Now all I want to see is some burnout from this coil. ^

Re: 8Kva Quad 833C VTTC
Dr. Drone, Sun May 27 2007, 04:30PM

Re: 8Kva Quad 833C VTTC
Dr. Drone, Tue May 29 2007, 06:38AM

Re: 8Kva Quad 833C VTTC
colin heath, Thu May 31 2007, 01:21PM

Wow Chris!!!! I cannot wait to see the beast in real life next march! That is looking a stunning coil
I hope my DRSSTC looks half as good although i doubt it.
Cheers
Colin

Re: 8Kva Quad 833C VTTC
ShawnLG, Thu May 31 2007, 05:12PM

This coil will come out really cool. I can't wait to see some VTTC ground strikes!

Re: 8Kva Quad 833C VTTC
Dr. Drone, Fri Jun 01 2007, 08:50PM

Re: 8Kva Quad 833C VTTC
colin heath, Sun Jun 03 2007, 01:52PM

well we have been looking at flights etc so looking good
Looking forward to it myself.
Anyway I had better stop hijacking the thread now
Cheers
Colin

Re: 8Kva Quad 833C VTTC
Dr. Drone, Thu Jul 12 2007, 12:29AM

Re: 8Kva Quad 833C VTTC
hvguy, Thu Jul 12 2007, 12:33AM

Damn you do good work Chris! Can't wait to see it run...

Re: 8Kva Quad 833C VTTC
Shaun, Thu Jul 12 2007, 04:06AM

I think I would always prefer see-thru interiors to those that totally block all view of the internal workings of the coil. I know making a good coil look nice can be just as hard as making a good coil to begin with, but you make both look easy.

Now you just need to stick an LED-lit fake flux capacitor in there and you can tell people its a time machine...

Re: 8Kva Quad 833C VTTC
J. Aaron Holmes, Thu Jul 12 2007, 05:00AM

Ha-haaaa! Awesome. This coil is going to be the image of brute force Can't wait to see how those Sangamo's hold out, Chris! Once I finish spreading out in the new house, I need to put mine to work. Bought four and had to take one out of the box to worship it for a few minutes

First light! First light!!!

Regards,
Aaron, N7OE

Re: 8Kva Quad 833C VTTC
ShawnLG, Thu Jul 12 2007, 05:43AM

Wow, that coil looks state of the art! Is the cat part of the coil? Also, what are those bank of red capacitors used for?

Re: 8Kva Quad 833C VTTC
Dr. Drone, Thu Jul 12 2007, 02:59PM

Re: 8Kva Quad 833C VTTC
Marko, Thu Jul 12 2007, 04:28PM

The crazy high-tech look of Christopher's stuff is just intimidating. I have absolutely no idea how you manage to design, cut and assemble all those small parts and have such a robust construction in the end.

Even if I had CNC CO2 laser cutter at hand it would take ages for me to build something like that.

Where did you find those fat (20mm or so, as I see?) plexi blocks? Plexi tubes? Until I saw your stuff I didn't know plexi tubes even exist. Thickest plexi I knew about was 8mm.

And how do you etch threads in plexiglass? That is impossible. Do you apply weld-on glue or CH2Cl2 on screws?

LED's...
I wouldn't put really too much led's on it - I think weak lighting would give it more mysterious look...

Good luck Miles

Re: 8Kva Quad 833C VTTC
dingo27, Thu Jul 12 2007, 05:41PM

Holy cow!!!
... i dunno how to write it - its SO HUGE (that behind you... or what he is on photo), as twice of me...
You are cutting that plexy really nice, also i like leds (you should use ultra... (mix red and white and you get color...) that sort of leds, like the sparks have. It should be much cool than this.
To TC - People, are you crazy? How much energy it sinks? xx W ? Round it to 10 (or 100 ? )
Nice job, ...

And i wanna know what is that silver kind of thing with two plugs on one side? (I now, maybe dumb question, but someone must write it )

Re: 8Kva Quad 833C VTTC
Dr. Drone, Thu Jul 12 2007, 07:53PM

Re: 8Kva Quad 833C VTTC
Finn Hammer, Thu Jul 12 2007, 08:03PM


Oh my god!

I don`t hope any goldfish were harmed during the production of your coils!

Cheers, Finn Hammer

Re: 8Kva Quad 833C VTTC
ragnar, Thu Jul 12 2007, 09:27PM


I've found with a good quality tap, I hardly ever get cracking or spalling of the plexiglass. You have to be more and more careful if you're tapping deep holes, though, and use some proper cutting compound or WD-40.

There are critical differences in design (and even more critical differences in material) between those $2 Taiwanese taps, and taps made in a reputable country with five times the price tag -- it makes all the difference.

Re: 8Kva Quad 833C VTTC
Dr. Drone, Thu Jul 12 2007, 10:23PM

Re: 8Kva Quad 833C VTTC
Ken M., Thu Jul 12 2007, 10:30PM

Yet, again you hold the reputation of Plexi glass god! The layout, and craftsmanship of the base is fantastic looking. You may have pointed it out and I just missed it or you didn't mention it at all, but will the secondary be on top of the base or will you or have you extended the base to have the secondary sit beside the tubes? Hell if you wanted you could offer to make your amazing bases for a price, especially since you enjoy doing it.

Re: 8Kva Quad 833C VTTC
kv, Thu Jul 12 2007, 11:03PM

WOOAH, great work!! i wish i had the supplies to build something like that!! i too enjoy making things more than running them, but this i want to see!!!!

Re: 8Kva Quad 833C VTTC
Bennem, Fri Jul 13 2007, 05:50AM

Wow Wow Wow!!.....and another thing....Wow!!!

That sure is one great looking construction!
The time, patience and effort put into it!!
I too enjoy construction possibly more than
seeing the working of a coil.
But i'm so looking forward to seeing pics of this baby working!
All the best Chris.

Mel.

Re: 8Kva Quad 833C VTTC
dingo27, Fri Jul 13 2007, 06:48PM

Well, i use normal, cheap (cheapest ... :) ) drills to cut plexi, but for cutting plexi with nice edges i use a special - mine developed tool. Put the battery metal off, knock it to nice flat piece of metal, cut it to to the round with hole in center, insert m3 screw into this, and you have little "saw". I use it with hand_driller (or how it is named) and i manage to cut nice line . I can also split a 2 mm plexi in a half :) with it. The little problem is heating, but it dont matter, because edges are getting cool in a second and with nice edges. If you have problem with speed, use knife to do some "tooths" on it - it will performance it.

Re: 8Kva Quad 833C VTTC
Dr. Drone, Fri Jul 13 2007, 07:25PM

Re: 8Kva Quad 833C VTTC
J. Aaron Holmes, Fri Jul 13 2007, 08:02PM


Wait, wait! ... How about "Rocky Valvoa"

Cheers,
Aaron, N7OE

Re: 8Kva Quad 833C VTTC
Steve Conner, Fri Jul 13 2007, 10:16PM

Triodosaurus Rex.

Re: 8Kva Quad 833C VTTC
Tom540, Sat Jul 14 2007, 12:01AM

LOL, Just doesn't get any geekier than that.

Re: 8Kva Quad 833C VTTC
kv, Sat Jul 14 2007, 12:42AM

some great names there!! (no, seriously) oh, now i really want to see this running!!

Re: 8Kva Quad 833C VTTC
Coronafix, Sat Jul 14 2007, 02:02AM


Perhaps he meant the little silver heatsinks on top of the tubes.

Re: 8Kva Quad 833C VTTC
dingo27, Sat Jul 14 2007, 04:56PM

I was thinking about this -


Mod edit- you're not allowed to post images wider than 400 pixels, so bleh

Re: 8Kva Quad 833C VTTC
Coronafix, Sun Jul 15 2007, 01:43AM

They're the microwave oven capacitors that he's painted
red in the assembled unit.

Re: 8Kva Quad 833C VTTC
Dr. Drone, Sun Jul 15 2007, 07:03AM

Re: 8Kva Quad 833C VTTC
Coronafix, Sun Jul 15 2007, 10:25AM

Plexisaurus Tubezilla is looking incredible, a lot of work involved there Doctor!
I see you are running out of room in your garage for these beasts,
You may need to build your own HV workshop!! :)
If this thing runs like other VTTCs, then will you need a 30 foot ceiling space to
run it in to accommodate the swords?!?
Love your work.

Re: 8Kva Quad 833C VTTC
Steve Conner, Sun Jul 15 2007, 03:57PM

You're right Goldsphere, it should be Triodosaurus Plex I was concerned by the lack of ceiling headroom too...

Re: 8Kva Quad 833C VTTC
Hazmatt_(The Underdog), Sun Jul 15 2007, 06:16PM

da VacuuNAtor

Re: 8Kva Quad 833C VTTC
Shaun, Tue Jul 17 2007, 12:48AM

Lack of ceiling space? Its in a GARAGE! Just open the doors and wheel it outside! That oughta scare away any dogwalkers, hehe.

Then again they won't appreciate it as much as we do.

Re: 8Kva Quad 833C VTTC
Dalus, Wed Jul 18 2007, 11:21PM

Would it be possible to audio modulate such a large vttc?

Re: 8Kva Quad 833C VTTC
Tom540, Wed Jul 18 2007, 11:23PM

ENOUGH JIBBER JABBER! FIRE IT UP ALREADY!

Re: 8Kva Quad 833C VTTC
Sulaiman, Thu Jul 19 2007, 01:47AM

Christopher,
I really hate your Tesla coils.








They make me jealous

Re: 8Kva Quad 833C VTTC
Kolas, Sat Jul 21 2007, 03:24AM

yes lets see some first light stuff already

Re: 8Kva Quad 833C VTTC
Shaun, Sat Jul 21 2007, 05:09AM

Everyone in this forum knows that rushing inevitably leads to fire...

Take your time, Chris.

Re: 8Kva Quad 833C VTTC
Danielle, Sat Jul 21 2007, 05:18AM

it dost always lead to fire. Usually you here 2 gunshots as your IGBTs fail, or your components blow up in some other way not always fire.

Re: 8Kva Quad 833C VTTC
Dr. Drone, Sat Jul 21 2007, 05:30AM

Re: 8Kva Quad 833C VTTC
Dr. Drone, Sun Jul 29 2007, 04:25AM

Re: 8Kva Quad 833C VTTC
sparky, Sun Jul 29 2007, 04:37AM

Looks like a great project... So you will be running 8kVA!? Really?? I didn't know you could get tubes at that size --- I guess you are paralleling several smaller tubes to get the desired current level... right?

Re: 8Kva Quad 833C VTTC
Dr. Drone, Sun Jul 29 2007, 04:44AM

Re: 8Kva Quad 833C VTTC
Wolfram, Mon Jul 30 2007, 03:20PM

Didn't know you could get 8kW tubes? Check out the Eimac 8974, it's capable of dissipating 1.5 megawatts. It's not very big physically.

Re: 8Kva Quad 833C VTTC
Marko, Mon Jul 30 2007, 04:14PM

*LOL* for the T-shirt inscription!

Eimac 8974

No need to be that greedy... and water cooling is a nuisance!

I think chris would be more than happy with something like this..

Re: 8Kva Quad 833C VTTC
Dr. Drone, Mon Jul 30 2007, 04:22PM

Re: 8Kva Quad 833C VTTC
Reaching, Mon Jul 30 2007, 06:51PM

Wow.

Mhh, time to dig out my Eimac 4-250A :)

Re: 8Kva Quad 833C VTTC
Steve Conner, Mon Jul 30 2007, 07:13PM

A VTTC with a MOSFET, whatever next! What does the MOSFET do, is it hooked between the tube cathode and ground?

BTW, it looks great already, I shudder to think what it'll be like with all four tubes firing

Re: 8Kva Quad 833C VTTC
Dr. H., Mon Jul 30 2007, 07:27PM

Hi to all coilers. I have been readin about VTTC for a long time and i have diceded to build one. I have about 40 russian lamps rated at 22kv 350ma. So i was wondering what i could achiev with them. Is it possible to post some more specs about your coil Christopher Miles.

Excuse my english - I am from Bulgaria

Re: 8Kva Quad 833C VTTC
WaveRider, Mon Jul 30 2007, 07:57PM

Wow Chris..I am impressed!

Steve, I once built an audio amp that operated a tube in "common grid" mode with a BJT driving the cathode. It worked quite well. In effect, it is very much like cascode topology. High gain with excellent isolation. The transistor only ever sees low voltage. I imagine this would work well as an audio modulator for a vacuum tube RF amplifier...like in an audio modulated tesla coil!

Cheers!!!

Re: 8Kva Quad 833C VTTC
Reaching, Mon Jul 30 2007, 08:56PM

mh, there is a shematic on a german website wich uses a mosfet to drive the screen grid of a pentode, wired as an rf oscillator driving a one coil plasmatweeter. Works just fine. This is the same magnat an some other factorys used in his plasmaspeakers

Re: 8Kva Quad 833C VTTC
Marko, Mon Jul 30 2007, 11:58PM

Hey, steve, I have zero experience with these things, but, How is such modulation actually done? Class A? If there was a point where mosfet is fully ''off'' and tube is ''on'', the mosfet would go ''bang''... ?

I also noticed people using triacs on the cathode itself for modulation, while using 4kV power supply? What prevents the triac from getting blown at that point?

Re: 8Kva Quad 833C VTTC
Dr. Drone, Tue Jul 31 2007, 04:25AM

Re: 8Kva Quad 833C VTTC
Dr. H., Tue Jul 31 2007, 06:15AM

My VTTC uses a MOSFET for the interupter, my lamps are penthodes and the MOSFET is connected to the second plate (I don't know how it is called in English) and i use it to pull the coltage on the plate to about -600v thus blocking the lamp. I use a simple interuptor and it works great :) .

Sorry for my english i am from bulgaria

Re: 8Kva Quad 833C VTTC
Steve Conner, Tue Jul 31 2007, 08:11AM

I guess "second plate" = screen grid?

Marko, turning the MOSFET or triac or whatever off will immediately turn the tube off too. The cathode voltage only rises until the voltage between cathode and grid is enough to stop the tube conducting, which is usually a couple of hundred volts.

Re: 8Kva Quad 833C VTTC
Marko, Tue Jul 31 2007, 07:40PM

EDIT: Now, if I understood this, as cathode voltage rises the screen becomes ''more negative'' to it, and ultimately cuts it off? And chatode-grid capacitance also discharges in process?

Re: 8Kva Quad 833C VTTC
Steve Conner, Tue Jul 31 2007, 09:00PM

Yes, you got it. Letting the cathode rise above ground amounts to the same thing as pushing the grid below ground.

Re: 8Kva Quad 833C VTTC
Coronafix, Sun Aug 19 2007, 10:43AM

Hi there Dr Spark,

Just curious to know how you're going on this project? I know you
are into the bipolar marx at the moment, is this because you
ran into issues with this project? You can tell me to mind my own business
if you want and that it's all in good time. I'm just a curious cat.

Myk

Re: 8Kva Quad 833C VTTC
Dr. Drone, Sun Aug 19 2007, 02:39PM

Re: 8Kva Quad 833C VTTC
Coronafix, Mon Aug 20 2007, 03:09AM

Glad to hear it's still on the go,
I'm sure I'm not the only one with bated breath on
what kind of sparks this thing will kick out.

Re: 8Kva Quad 833C VTTC
Dr. Drone, Tue Aug 21 2007, 05:49AM

Re: 8Kva Quad 833C VTTC
Myke, Tue Aug 21 2007, 06:05AM

Very nice again. Keep up the good work. Your workshop is so clean too.

Re: 8Kva Quad 833C VTTC
Ken M., Wed Aug 22 2007, 12:28AM

That is incredible Chris, now we just need and want the pics with arcs! Still looks awsome!

Re: 8Kva Quad 833C VTTC
Dr. H., Wed Aug 22 2007, 11:42AM

Very nice . Waiting to see some great sparks

Re: 8Kva Quad 833C VTTC
J. Aaron Holmes, Fri Nov 02 2007, 05:22AM

Bump.

Chris: Any updates? It's taken great feats of personal restraint to avoid asking for this long ...I mean... if it all blew up, it's still worth sharing... we can all learn from these things (taunt, taunt, taunt) ))

Cheers,
Aaron, N7OE

Re: 8Kva Quad 833C VTTC
Dr. Drone, Fri Nov 02 2007, 05:51AM

Re: 8Kva Quad 833C VTTC
Dr. H., Fri Nov 02 2007, 01:40PM

Chris i was wondering for such a power what will be the specs of the primari circuit (MMC and number of windings ? )

Re: 8Kva Quad 833C VTTC
Dr. Drone, Fri Nov 02 2007, 10:27PM

Re: 8Kva Quad 833C VTTC
J. Aaron Holmes, Sat Nov 03 2007, 12:03AM


YAYYYYYY!!! I'm very glad to hear it. I have four of these same caps, one or more of which will undergo "first light" here pretty quick. I know that ~3x the plate voltage is supposed to provide for a pretty conservative tank cap rating, but I'm still nervous as hell about using just one of them because I have no idea where I'd find another nice new one if I blew one of them up! (having an odd number would suck!) And at the same time, using all four in a single-tube ~1kW coil for 2.4nF @ 40kV @ 48A would be EXTREEEEEEEEEEEEEME overkill!! BUT...I may do it anyway

Cheers,
Aaron, N7OE

Re: 8Kva Quad 833C VTTC
Dr. H., Sat Nov 03 2007, 09:22AM

Hi Chris. Thanks for the reply. If you have seen my thread about the 4kAV VTTC you will see that i have very simmilar mmc (2,8 nF at 30 000v ) but it si enormous in size my also i a extreeeeme overkill

Re: 8Kva Quad 833C VTTC
J. Aaron Holmes, Sun Nov 04 2007, 12:57AM


OTOH, "extreeeeeme overkill" in the tank cap is probably a happy thing. Having your tank cap be the toughest part of your setup means that everything else will blow up first (which is great if the other parts are cheap The caps often aren't.)

These Sangamo mica caps are physically huge, hence my original "overkill" comment:



They're bigger than soda pop cans and weigh almost 2kg each. They're ancient history too, so they go great with glass tubes These are the same caps Chris is using for his beast, AFAIK. Mica caps seem to be much larger than similarly-rated ceramics. It will be interesting to see if the higher temperature stability of mica proves advantageous, although I asked Steve W. about this once and he said he'd never observed any heat-related detuning in his coils, and he's used strontium titanate (SrTi) caps exclusively. That is goodness in general, since they've lately become available very cheaply on eBay.

Let's hope Chris gets bored with his Marx generator pretty quickly here I can't wait much longer. I need quad-833C action!!

Cheers,
Aaron, N7OE

Re: 8Kva Quad 833C VTTC
Dr. H., Sun Nov 04 2007, 08:15AM


I fully agree. Everyone hire wants to see that beast in action.
That's amazing cap Aaron. I love it . It's look more like a hand grenade than a capacitor, but once again I LOVE IT

Re: 8Kva Quad 833C VTTC
Dr. Drone, Wed Nov 28 2007, 02:15AM

Re: 8Kva Quad 833C VTTC
..., Wed Nov 28 2007, 03:52AM

!sad

Have you considered like adding some nice big rubber tires or something as to avoid tearing it apart? A little winch on the front to get it up the ramp

Good luck!

Re: 8Kva Quad 833C VTTC
Dr. Drone, Wed Nov 28 2007, 05:20AM

Re: 8Kva Quad 833C VTTC
Zum Beispiel, Wed Nov 28 2007, 03:17PM

I'm waiting desperately for you to finish this monster! I want to see those big 8kVA sparks

One thing that has been buggin me though: Your secondary looks pretty thin for such high power? I know next to nothing about VTTCs, so are the secondaries usually smaller on VTTCs? Or does it just look small because the base is so huge?

Anyway, good luck on getting the beast running

Re: 8Kva Quad 833C VTTC
Dr. Drone, Wed Nov 28 2007, 04:39PM

Re: 8Kva Quad 833C VTTC
Dr. Drone, Fri Jul 18 2008, 11:13PM

Re: 8Kva Quad 833C VTTC
Marko, Fri Jul 18 2008, 11:25PM

Hi dr. spark!

Sorry to see your problems with oil tank - that must be frustrating!

Watching at this coil for some time - why did you decide to go with *crappiest* transformers in production -MOT's, while $ is less of a problem to you and I would think a coil of that size would deserve a dedicated filament transformer - small pole pig, or PT? I know you have at least 1 pig around?

Still after all this cool work I guess you want to fix the mot tank.


I'm jealous of all your cool glass tubes, I've just realized what a pain in the ass it is to house and cool ceramic tubes.

Marko

Re: 8Kva Quad 833C VTTC
Dr. Drone, Fri Jul 18 2008, 11:41PM

Re: 8Kva Quad 833C VTTC
Marko, Fri Jul 18 2008, 11:58PM

Oh- how you mean ''the coil was not happy''? Tubes overheating, shorter sparks? Did you use level shifter with it as well?

In any case I don't understand why would it be worse too high, too low voltage?


For 230V mot's meh - there are plenty in Europe and they don't really look like quality, ah paper insulation!

Marko

Re: 8Kva Quad 833C VTTC
Dr. Drone, Sat Jul 19 2008, 12:10AM

Re: 8Kva Quad 833C VTTC
Marko, Sat Jul 19 2008, 12:33AM

Chris, have you checked this thread?



The guy from denmark has 12 equal MOT's, all 230V ofcourse.

But in any case, unless you are using a single MOT, what's wrong with simply seriesing primaries of two 120V MOTs?

Regarding the frequency, it's really irrelevant difference between 50 and 60Hz. And 50Hz MOT will only work better on 60Hz in any case...


Still you really think it's worth to ship MOT's across Atlantic? I 'd never even think about that, too much weight!

But MOT's aren't plentiful in Croatia either, I only have a single one here, no organized salvage or anything.

Just curious, where are you going to get your 200A supply? If I needed 8kW, wouldn't an easier first step be to use 3phase supply?
Is it crucial for you to have single-phase halfwave rectified input, for this coil?

Re: 8Kva Quad 833C VTTC
HV Enthusiast, Sat Jul 19 2008, 12:34AM

Check out Martin Microwave Inc.
I've always purchased matched transformers from this guy inexpensively. Not sure if he has 240VAc transformers though, but he has lots of stuff.

Re: 8Kva Quad 833C VTTC
Dr. Drone, Sat Jul 19 2008, 12:48AM

Re: 8Kva Quad 833C VTTC
Mads Barnkob, Sat Jul 19 2008, 05:56AM


Shipping 10kg to USA would cost about 100-120$, for that money you could properly buy two new identical MOs instead :)

Re: 8Kva Quad 833C VTTC
Dr. SSTC, Sat Jul 19 2008, 07:03AM

well im no expert but maybe you could use solid state microwave transformers like kreso ljubiov

Re: 8Kva Quad 833C VTTC
KresoLiubov, Sat Jul 19 2008, 08:12AM


Maybe he could. I almost finished designing my SS driver. I saved all in a drawer because i will work on DRSSTC more. The 833 seems impossible to get, so i let the project on standby

Re: 8Kva Quad 833C VTTC
Dr. Drone, Sun Nov 16 2008, 10:08PM

Re: 8Kva Quad 833C VTTC
..., Sun Nov 16 2008, 11:43PM

The youtube like is broken

Re: 8Kva Quad 833C VTTC
Arcstarter, Sun Nov 16 2008, 11:51PM

It worked alright for me.. Hmmm, did someone already fix it?

Re: 8Kva Quad 833C VTTC
teslacoolguy, Mon Nov 17 2008, 12:41AM

worked for me to.