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Vacuum tube tesla coil HELP

Epiccow400

Oct 9, 2023
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Hello, i built a dual 811a vacuum tube tesla coil using steve wards VTTC 1 design. My build does not work. Can someone please look over my circuitry and check it against the schematic below? however shoddy my connections look they are solid and tested. I am inexperienced with electronic schematics but know how to be safe with high voltage. Anyone with tesla coil experience could please help me with this? My vacuum tubes light up and my primary seems to be getting power, but no sparks on the secondary. I have tried swapping connections on all the coils and have ran out of ideas. Any help is welcome, thanks.IMG_7266.jpegIMG_7338.jpegIMG_7339.jpegIMG_7340.jpeg
 

kellys_eye

Jun 25, 2010
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What value are the three blue capacitors in series across the 50W resistor? You do know that the values don't 'add up' when they are wired in series?

Other than that I'm not happy telling people how to kill themselves. That MOT looks dangerous a f***

I'l assume that if we don't hear back from you that you got it working and are now dead.....
 

73's de Edd

Aug 21, 2015
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The series caps need to each be ~5.6n to be close to that value you show to be needed.
Another consideration is the, easiest to work with, small wire gauge feedback winding, try a shift in feedback phase by reversing its two wire ends positions.
Considering that you are not a "lefty" both of them appear to be ENDS or STARTS of both of those windings.
THEN pre-warm up the 811 filaments and THEN do a quick HV turn on, to see if the unit oscillates. . . . . . . if you don't . . . . . . first.

I certainly don't like to see that HV level screwed into a RAW? pine board ...... .....
 
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Epiccow400

Oct 9, 2023
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What value are the three blue capacitors in series across the 50W resistor? You do know that the values don't 'add up' when they are wired in series?

Other than that I'm not happy telling people how to kill themselves. That MOT looks dangerous a f***

I'l assume that if we don't hear back from you that you got it working and are now dead.....
The series caps need to each be ~5.6n to be close to that value you show to be needed.
Another consideration is the, easiest to work with, small wire gauge feedback winding, try a shift in feedback phase by reversing its two wire ends positions.
Considering that you are not a "lefty" both of them appear to be ENDS or STARTS of both of those windings.
THEN pre-warm up the 811 filaments and THEN do a quick HV turn on, to see if the unit oscillates. . . . . . . if you don't . . . . . . first.

I certainly don't like to see that HV level screwed into a RAW? pine board ...... .....
I just changed them to 3 2kv 6.8nf capacitors in series. Tried again and switched polarities of each coil one at a time and still nothing. I really appreciate the help in trying to get this to work. Any more tips or something im doing wrong? Thanks
 

73's de Edd

Aug 21, 2015
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Sir Epiccow400 . . . . . (and I don't thinks that I done evers met up with an epic cow befores . . . just plain milk cows)

You only needed to change . . . . the easier to work with . . . . fine wire ends of that smaller, top feedback coil.
Get that 2KV plus off those screws and bare board and onto a supported homemade Lucite insulator terminal.
PLUS . . .
Learn about the TRUE intimacies of an 811 . . . . . . its grid is NOT where you have it connected to . . . . BUT . . . . . you got the filaments and plate correct ! . . . . . . .however . . .pwecawious (Elmer Fudd) those slippy-wippy alligator clips are looking.
1696892687263.png
Place "El Tubo" with its base facing you and its plate cap being un viewable and then first right top corner BIG pin is #1 then clockwise small pin is #2 then #3 for next small pin and finally #4 for last large pin.
Thaaaaaasssit . . .


My preconceived ESP response . . . . . . . you're welcome.


73's de Edd . . . . .

Can any others, equally CONFIRM . . . that . . .

Having a teenage daughter is like having a cat that only comes out to eat and hisses when you try and be nice to it.

.
 
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Epiccow400

Oct 9, 2023
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Sir Epiccow400 . . . . . (and I don't thinks that I done evers met up with an epic cow befores . . . just plain milk cows)

You only needed to change . . . . the easier to work with . . . . fine wire ends of that smaller, top feedback coil.
Get that 2KV plus off those screws and bare board and onto a supported homemade Lucite insulator terminal.
PLUS . . .
Learn about the TRUE intimacies of an 811 . . . . . . its grid is NOT where you have it connected to . . . . BUT . . . . . you got the filaments and plate correct.
View attachment 60970

Preconceived ESP response . . . . . . . you're welcome.


73's de Edd . . . . .

Pls also CONFIRM . . . that . . .

Having a teenage daughter is like having a cat that only comes out to eat and hisses when you try and be nice to it.
Thanks for the response. Grid is 3 correct? I think i have that right. Check the pictures if you can.
 

73's de Edd

Aug 21, 2015
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Checking your last pick-choor and viewing the more panoramic and revealing 2nd 811's perspective.
1 . . . . . RED al-la-ma-gator clip is affixed and biting into LARGE pin #1
2 . . . . .End of feedback coil wire initially goes to the first 811 and then out and over
to make a wrap around and soldering? to small pin #2 (unused connection)
3 . . . . . Small Pin #3 . . .THE real grid connection, is being unconnected and it screaming . . . HEY . . . HOW ABOUT ME ?
4 . . . . . BLACK al-la-ma-gator clip is affixed and biting into LARGE pin #4

Thaaaaaaaaassssssss-still-it . . . . . .
 

Epiccow400

Oct 9, 2023
5
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Messages
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Checking your last pick-choor and viewing the more panoramic and revealing 2nd 811's perspective.
1 . . . . . RED al-la-ma-gator clip is affixed and biting into LARGE pin #1
2 . . . . .End of feedback coil wire initially goes to the first 811 and then out and over
to make a wrap around and soldering? to small pin #2 (unused connection)
3 . . . . . Small Pin #3 . . .THE real grid connection, is being unconnected and it screaming . . . HEY . . . HOW ABOUT ME ?
4 . . . . . BLACK al-la-ma-gator clip is affixed and biting into LARGE pin #4

Thaaaaaaaaassssssss-still-it . . . . . .
OMFG DUDE IT WORKS!!!! THANKS SO MUCH MAN!!!
 

73's de Edd

Aug 21, 2015
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I SAY ! methinks . . . . . somehow . . . . . . ¿ maybe ? . . . . . that . . . . .
OMFG DUDE IT WORKS!!!! THANKS SO MUCH MAN!!!
is estimably highly over equating . . . . my initially submitted supposition of . . .

My preconceived ESP response . . . . . . . you're welcome.

NOW . . .you need to degrade and defuse that potential DEATHTRAP !
Get one of those clear HDPE or clear vinyl storage containers to invert and cover your board and have a round cut out for the Tesla HV winding to pass thru.
Then have the inverted cover screwed down to the board.
Also relay back to us which one of the set of fine gauge feed back wires bottom-start or top-finish . . . ended up getting connected to the grids permitting the unit to oscillate then. (That's overlooking the pin 2 and 3 quandry . . . D U U U U U H ! )
That can help others to begin with .

1697016254904.png







Also ? are you aware that unit may be wired so that it is STILL not achieving its potential max output ?
Query me . . .if needed . . .

73's de Edd . . . . .

I finally done it . . . .
I had the frog in my backyard pond DNA tested . . . it turns out he's mainly part Irish, part British, and just a tad Pole.

.
 
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Epiccow400

Oct 9, 2023
5
Joined
Oct 9, 2023
Messages
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I SAY ! methinks . . . . . somehow . . . . . . ¿ maybe ? . . . . . that . . . . .
OMFG DUDE IT WORKS!!!! THANKS SO MUCH MAN!!!
is estimably highly over equating . . . . my initially submitted supposition of . . .

My preconceived ESP response . . . . . . . you're welcome.

NOW . . .you need to degrade and defuse that potential DEATHTRAP !
Get one of those clear HDPE or clear vinyl storage containers to invert and cover your board and have a round cut out for the Tesla HV winding to pass thru.
Then have the inverted cover screwed down to the board.
Also relay back to us which one of the set of fine gauge feed back wires bottom-start or top-finish . . . ended up getting connected to the grids permitting the unit to oscillate then. (That's overlooking the pin 2 and 3 quandry . . . D U U U U U H ! )
That can help others to begin with .

View attachment 61007







Also ? are you aware that unit may be wired so that it is STILL not achieving its potential max output ?
Query me . . .if needed . . .

73's de Edd . . . . .

I finally done it . . . .
I had the frog in my backyard pond DNA tested . . . it turns out he's mainly part Irish, part British, and just a tad Pole.

.
Hmmmmm… yesssss….. the bottom of the feedback coil is what goes to the tubes pins. Looking into that storage container cover now. Still not achieving max output you say? I would say so since i did blow up my tank capacitor (Ordered a better one). What would you reccomend i change on the wiring? Thanks.
 

Delta Prime

Jul 29, 2020
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What would you reccomend i change on the wiring? Thanks.
Cease and desist.
The factoid that you asked that question doesn't seem to raise any flags! But with me it does.
Seems to me the hobbyist is unaware of the known dangers involved when working with high
voltage.
I would think some degree of existing experience is inferred(He has none).The OP lacks insight to work safely with Tesla coils. But my mind is at ease because this site accepts no legal responsibility for any personal injury.
This guidance is careless senseless and irresponsible. It is easy to forget the other novices electronic enthusiasts will read this thread. You're Tupperware idea ain't going to cut it. The thread starter should engage in another line of interest for his or her own safety.
All you're doing is making it wideband RF jammer. But I would be a hypocrite to say it's not fun. I did the same thing when I was 14. I am 28 years old...I had the idea when I was 13 and it took me a year to acquire the knowledge to make my Tesla coil (far more powerful than yours but just as dangerous).
 
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