Vostok 3.0 Vacuum Tube Tesla Coil Demo + Theory Of Operation

[@FredtheDorfDorfman1985]

Beautiful setup, a work of art. You're like me, you don't want to just throw something together that looks like something the cat dragged in out of the junkyard, you want to make something beautiful to look at whether it's on or not. Impressive!

[@MrElapid]

Beautifully crafted! I put the same 100w. resistor on my 833A coil for grid drain but bought a variable one with a slider. Ended up around 5K but fun to play with. .

[@TheCrazzyToobinator]

That is one of the neatest wired set ups I ever did see

[@Extelec]

I am truly envious of the size of your workshop

[@SteveLane]

ot belongs to my father and he wants space just now to restore 3 classic motorcycles... if that makes you feel better!

[@whatelseison8970]

I could be wrong but it sounds like this thing is configured as an Armstrong oscillator, not a Hartley. The defining feature of a Harley is a tank with a tapped inductor and single cap and is the dual of the Colpitts with a pair of caps and a single coil, whereas an Armstrong has a main coil with a cap across it forming the tank and a separate tickler coil loosely magnetically coupled to it driving the active component; just like this. Cool stuff though and nice workmanship!

[@SteveLane]

Good spot, you are indeed correct! Seems I was thinking about Hartleys around the time I made this video, however I must have gotten the two mixed up during the video (how things usually go...), But yes it is an Armstrong in actuality, it is based of one of Steve Wards original 833 tube VTTCs, which is undoubtedly an Armstrong. Thanks for the correction, I should update the description for anyone else interested in building such a circuit. Cheers! 👍

[@John-HighVoltageProjects]

Very tidy as expected ,glad you made good use of the massive MOT I gave you ,knew it was better of with you and this is exactly why !Great work dude love it .

[@John-HighVoltageProjects]

Hahahaha well it's great that it's being used ,not just sitting on the floor of the shed .It is massive but well worth taking the extra space to give a lot longer run time although I would have loved to see a conveyor running, I think on the practicality side of things it would have been a proper pain in the arse lol .

[@SteveLane]

Haha yeah carbon brushes to pick up on as they align into the coil then all the way out the door on a conveyor to cool off outside... Oil immersion would have been the other option as the fan was just too noisey over a VTTC and would need two to cool the otherside, unless I rotated it on a microwave turn table... =]

[@DrakeMonroe]

I could be mistaken but I believe what you are smelling is Ozone. I have a small industrial light tester that's basically a tiny Tesla coil. It splits O2

[@SteveLane]

Yes that is true, I know the fluorescent light testers also we had one of those at work before LEDs became mainstream.

[@SUDExperiment]

How to make it sir

[@SteveLane]

Check out vttc examples on Steve Wards site stevehv.4hv.org that should get you started! 👍

[@SUDExperiment]

Ok sir thank you

[@ridefast0]

That's a very tidy build, great! Nice to see AC operation for a change; simpler design and could even become push-pull; its a shame you couldn't reuse the MOT filament winding for the filaments; you could have just the one mains transformer and still wind everything up slowly on the variac! Stiffies not withstanding of course (as per the strange comment below).

[@SteveLane]

Thanks Ridefast! That's not a bad idea about the filament transformer actually, around the time I build this, I had intention of using a staccato controller to modulate the output, so probably the idea of supplying the electronics also via the HV transformer didn't even enter my mind. Coincidentally I'm exhibiting this little favourite at Wellend Steam Rally this weekend in the stat engine section, powered by an old generator of course. =]

[@brandoncochrone5582]

I would love to see a much smaller analog Tesla coil build for getting into the hobby there all sorts of videos for Slayer exciters but not many informative videos for real analog Tesla coils

[@SteveLane]

Generally speaking, silicon based electronics are smaller than their equivalent thermonic emission predecessors (vacuum tubes) by their design intentions. 811 triodes are thought of as being small in their relative size to others. I am intrigued by the thought of a small scale VTTC, there are definitely smaller vacuum tubes than the 811 triodes, however I would speculate the limiting factor with vacuum tubes would be the much higher frequencies required to match the resonance of the smaller coils. I'm no expert on vacuum tubes though, so I wouldn't give up on this idea based on my speculation.

[@Max_Chooch]

That's one hell of a bug zapper

[@illumiNOTme326]

Wow that is a thing of *BEAUTY*

[@TeslaExplorer]

enjoyed watching and listening to the details. hope you've been well!

[@kaboooom2000uk]

Good to see more tesla coil enthusiasts from the UK. What inspired the name?

[@SteveLane]

The name was a combination of the general shape, the use of many russian sourced components and things that occurred during the vacuum tube era. Check out Gaussfest or teslathons in the UK, worth signing up to the exhibiters list with your TC. 👍

[@vitaliydrobina9394]

Beautiful set!

[@VariacManiac]

That's creative;DD Having the vacuums on each side of the coil for a bit of style!!!!

[@SteveLane]

Based it loosely on an old vacuum tube audio amp, but also putting the tubes anywhere else doesn't allow the heat to rise from then quite so easily. The glow reflected on the coils is an added bonus that makes it in my opinion.

[@VariacManiac]

Steve Lane Yeah, that too, nice output, and coil;DD Thanks For Showing, Cheers Mate!!!!

[@hiseminencetheholymacdiarmada]

Looks pretty awesome, sparks are always kickass... I'm too dumb to understand all that technical talk though

[@hiseminencetheholymacdiarmada]

I don't remember posting this comment!! Sounds about right though...

[@OrbiterElectronics]

Very nicely built that Steve. I like it. Cheers John

[@SteveLane]

+orbiter8 (John) Funny thing is that it was only meant to be a "Proof of Concept" build, hence the ply wood and nylon standoff construction... It was a few weeks after Cambridge Teslathon in late October last year I plugged my first vacuum tube in after noticing the lack (precisely zero) of Vacuum Tube Tesla Coils at these events. About a month later I had it oscillating for the first time putting out about 3-4" arcs, then after some problems with a dodgy vacuum tube I was managing 6-7" arcs just before Christmas. Then spent the next two months trying to get an interrupter to work for pulsing the arcs at lower rates to increase the output length, but with not too much success. So with only a month left til Nottingham Gaussfest, I decided to build my current setup into a unit and roll with that despite the few bugs in the circuit I have yet to still iron out... =]

[@EnergyFabricator]

Works nicely & looks great too!

[@SteveLane]

+Energy Fabricator Thanks! I have yet to sort out a few bugs in the circuit before moving on, so stay tuned for updates!

[@davestewart2433]

May I ask how many turns were on your secondary, roughly. Thanks.

[@SteveLane]

Hi Dave, it's been awhile since this build, digging though my notes led to nothing, but that's most likely because I used a spare secondary from my original SGTC build, which means it is very likely to be 1113 turns looking at those notes.

[@davestewart2433]

@@SteveLane no worries. Thanks for responding. hope you are still coiling. I have done spark gap, SSTC and now embarking on VTTC. Your design inspired me so much, it's beautiful. I am sourcing the parts each day. Thanks.

[@SteveLane]

@@davestewart2433 You're welcome! I'm still coiling actually, I exhibit only once a year at Wellend Steam Really of all places, it's local to me! Likewise, at least 90% of the time is spent sourcing parts, I bought a massive sheet of 10mm tufnol this year with a vision of rebuilding the wooden frame this VTTC is made out of, you might think unnecessary, but the way the light shines off it is beautiful! Let me know if you get stuck anywhere, I'm more than happy to lend my own experiences etc. 👍

[@davestewart2433]

@@SteveLane I sure will, thanks. Ttufnol, I had to look it up. It's nice stuff. Please post more videos when you finish the rebuild.

[@SteveLane]

@@davestewart2433 Will do! I need to start filming more, even just exhibitions... Lack of time is the biggest issue these days, usually due to too many simultaneous projects. You have a great channel btw! I was looking for the comments, but I guess you have them off?

[@tuopeeks]

Nicely put together. In my set up I used a full wave rectifier on the MOT and some smoothing just to feed DC to the tank circuit. Looks like I don’t need to. :-) Inspires me to have another go at improving the output on mine as I like the nice quiet output with VTTCs.

[@SteveLane]

+tuopeek1 A "quiet substation" is a favourite way to describe the sound to people. A smooth DC supply will make it easier to get a clean signal to audio modulate if you ever wanted to attempt that on a VTTC. VTTCs are very therapeutic to work with, I could could work on them all day if I could. =]

[@T2D.SteveArcs]

You tried a filtered supply Kram? Do you have any video of it running mate.. .... hi Mr Lane, this is a really pretty coil, I'm sure ive told you that before 😅,....

[@tuopeeks]

@@T2D.SteveArcs Think I've tweaked my psu a few times since this comment. I decided a smooth DC supply doesn't result in a good coil output as you know🙂.

[@T2D.SteveArcs]

@@tuopeeks oh yeah I know it doesn't give the best output mate I just wondered what it was like with smooth filtered DC.. il DM you soon mate I'm very sick atm...

[@tuopeeks]

@@T2D.SteveArcs 😯hope you get well soon

[@martinmikulcik7350]

It wasn't high freqency ,it was 50 or 60 Hz.

[@SteveLane]

Hi Martin, You are correct that this VTTC runs on 50Hz AC, but there is also a resonant frequency of the secondary coil that is in the realms of 300 to 400kHz, it's this frequency that enables the high voltage arcs to break out from the topload that you see when it is running. Because 300-400kHz is beyond what is possible to hear, it's the 50Hz you hear. Interestingly the high frequency rides the low frequency waveform like a carrier frequency. Kind regards Steve

[@Mr_Flybacker]

Soviet K15U-1 caps. From Russia with love)

[@dirkk82]

ahh steve she's a beaut ! nicely constructed i might say but then again you always show off your craftsmanship ! still going for a quad tube setup ? always forget to ask in chat :-p and only 6 amp draw ?! crazy, pretty efficient circuit or just because its a smaller coil, not sure how that works really :-p anyway talk laters cheers !

[@SteveLane]

+dirkk82 The plan seems to change every time I learn something new to how to run my Coil more efficiently, at the moment I get an inch of arc for every amp of current I put in, which compared to SGTCs is very inefficient, but for VTTCs is not too bad, they're so power hungry and sound like a substation but I do love the way they look and sound, all warm and fuzzy! =]

[@greenthizzle4]

Steve Lane look into other vacuum tubes for that, there are better kinds that have extra grids and stuff

[@arcsound.]

Very cool!

[@Alexelectricalengineering]

Nice !! Thumbs up !! Alex

[@SteveLane]

+High Voltage Thanks Alex!

[@Alexelectricalengineering]

Steve Lane 👍👍👍👍

[@ElectronHVChannel]

neat =)

[@SteveLane]

+ElectronHV Cheers!

[@LutzSchafer]

Well, you are running this thing without rectifier. So only the top part of one halve wave of the power supply will cause your circuit to oscillate and giving the 30Hz humming sound. You could get a lot more output by using a full wave rectifier with some microwave oven HV cap's in parallel. Looking at Steve's schematic and assuming its the same as your build, I see rather a classical Meissner oscillator than a Hartley one, but that does not matter much. Yeah, a push/pull may give you twice of what you have now, but is still not optimal as both tubes are only permitted to oscillate on a short duty cycle with varying power output. You need to be careful not to cause a current through the grid (e.g. by positive potential on it). This is a) not good for your tube (heats up the grid) and b) does not further increase plate current. The grid resistor (50W, really?) limits this current, but it would be better to build your circuit to avoid grid current all together.Otherwise, I admire your great mechanical workmanship. It is indeed an eye candy :)

[@SteveLane]

LutzSchafer First off, thanks for your critique of the electrical design of this build, its great to find someone who understands these devices better than myself! I hope you can appreciate this is by no means perfect as it was my first attempt at VTTCs, (very) loosely based on one of Steve Wards early projects. Secondly, I could and probably should have ran on DC, but during the breadboard stages, I did find the anodes would warm up quite significantly during short runs, so keeping the supply AC was a cheat way of limiting the power... Obviously there is other means of limiting the duty cycle of the tubes, but at the time I was already halfway there without having to change anything. So you are saying to go DC and use the grid feedback tuning to manage the duty cycle for a more constant output?

[@LutzSchafer]

Steve, tube designs remind me of my early days in electronics. While they were still taught partially during my educational years, the focus really turned to semiconductors. Working for many years in circuit design and after changing career to optics development, i feel overcome by nostalgia when seeing that people work with good old electron tubes. 30 some years back I worked for a diathermy company and that was the last time I professionally developed their shortwave power oscillator (which was a Hartley) using a power triode with graphite anode. The max output was 500 watts if memory serves me right. To your Tesla transformer design, I agree that a too high bias current will heat up your plate. High power transmitter triodes usually have heat sinking capabilities or graphite anodes that are allowed to get hot. When running on DC you could try to bias down the tube towards B or C type. This would give you less current draw but same output swing. Might be a good idea to spice simulate everything. Back in my days simulation was just in the beginning. I can only talk from my agend old experience and from a time where we learned to design DC bias as well as RF by hand. In your case it would be nice to have the proper high voltage oscilloscope probes so you can actually see what is going on with removed secondary of course. Anyhow I wish could be of more help. I can try with basic electronic design principles but that you likely find online and/or know yourself. I just found your design intriguing because of running on ac. Back in my days I might have failed my courses for such rather unconventional use.