Nst transformer?

How do I find out how much current my transformer can drive? How do I compare the drive of my transformer, and what's the purpose?

Asked by wiccakingkamui 5 years ago  |  last reply 5 years ago


Testing a NST with a DMM?

I have been looking for a good (and cheap) NST for a while but i dont want to risk spending too much on a NST that doesnt work. I know that my local scrap yard has a large supply of old NSTs that are either there because both or one side doesnt work, they were upgraded, or someone needed the money and/or space. i also know that they would frown upon me wiring each one up and testing each. so onto the real question: is there a way to test a NST with just a multimeter and possibly a battery (i know thats how some people test for flyback transformer pins) or if checking continuity would be enough or even another way? Just so everyone knows i have spent quite a while searching for someone using this technique but didnt find anything, also im looking for a way to know for sure if one or both sides are working.

Asked by pmk222 3 years ago  |  last reply 3 years ago


NST in tesla coil

Hey,I was thinking of making a Tesla coil for my science fair.The fact that NST (neon sign transformer) are a bit expensive, could anyone suggest me another way for its power supply other than using it

Posted by Энтони 2 years ago  |  last reply 2 years ago


I got a NST!

I recently bought a 11kv, 30mA Neon Sign transformer. I can get nice arcs off of it and everything (maybe about 2 inches? when rectified it makes shorter high pitch arcs), but I'm wondering about protecting it. after a couple hours of playing with it there was a loud pop in the case and it stopped working. I opened it up (it was held together by rivets, I just drilled the rivets out) and it's a switched mode neon sign transformer. I thought it was a bit light! So I found a (transistor? To-220 case) that had it's face blown off, luckily I found the other piece and I'm going to order the component and replace it. So, is there a cheap easy way of preventing this happening? While opening the case I added a number of saftey features, a saftey switch, and a "ON" indicator.

Posted by guyfrom7up 10 years ago  |  last reply 10 years ago


nst for tesla coil?

How do I get an nst and for a jar capacitor do line the inside or just leave a straight diode down the middle

Asked by wiccakingkamui 5 years ago


Possible to hack a NST with sGFI?

I'm having a really hard time finding an old neon sign transformer (NST) for high voltage (HV) experiments. Almost everything on craigslist is of the newer transformer that has the secondary ground fault protection.  So is there a way to hack the new ones?  I appreciate and thank you in advance for your help.

Asked by JeffB23 3 years ago  |  last reply 3 years ago


Are the old metal cased NSTs filled with tar? Answered

I've got an old NST and am interested in removing the shunts, before I do anything I would like to know if they (old NSTs) are filled with tar? It is a 12kV 23mA.

Asked by The MadScientist 7 years ago  |  last reply 7 years ago


Can anyone help with troubleshooting a tesla coil?

After working on a tesla coil off and on for a few years I finally finished building one, but it is running into several problems. The only problem that I can't figure out is that despite following the basic tesla coil diagram the toroid will not create a jumping spark; however the gap generator still produces a spark. The coil is running off of a 15kv nst with a gfi built in.

Asked by Kaptia Teramo 3 years ago  |  last reply 10 months ago


What can I do with this transformer from a 4 wheeler? Answered

 This is a working (I think) and I just wonder if I can wire it up and get some voltage for like a jacobs ladders or just a small arc?

Asked by j.hawkins 8 years ago  |  last reply 8 years ago


I'm getting a 12kV 30mA neon sign transformer, How do I make the output variable so I can turn the power up or down?? Answered

Title says it all how do I make it so I can turn the power up or down? thanks for any help =D

Asked by j.hawkins 8 years ago  |  last reply 8 years ago


Stupid Question - Neon Sign Transformer for Tesla Coil? Answered

I probably already know the answer to this question, but I'll ask it anyway. For a Tesla Coil, the NST's input power supply generally comes from a 120 V outlet, right?

Asked by Umniscient 8 years ago  |  last reply 8 years ago


Neon Sign transformers, gotta go! $40 each.

These things have been sitting in my basement for quite a while; I doubt I'll ever use this many. So, I offer them for sale! I've got 9,000V ones, 7500V ones, 6,000V ones, 5,000V ones and 4,000V ones. $40 each. All are 30mA, center tapped with no sGFI, perfect for Tesla coils, Jacob's ladders, etc.

Posted by grenadier 6 years ago  |  last reply 6 years ago


Does the size\weight of an NST matter? Answered

Hi everybody, I have at work two old school iron core neon sign transformers. They are both rated at 10KV 100mA. The thing is, one of them is only 2/3 of the size and weight of the other.   Assuming they are both in good condition, would there be any difference in performance, durability, reliability or whatever between the two?   I want to build a Jacobs ladder, and was wondering which one would work best... Thanks for the help!

Asked by Morgantao 5 years ago  |  last reply 5 years ago


Ways to make an Asynchronous Spark Gap NST friendly

Are there any ways to protect your neon sign transformer(s) from the affects of an Asynchronous rotary spark gap?

Posted by OzoneLab 6 years ago


Looking for high voltage transformer(s)

Hi! I am looking for anyone who would be willing to give me any neon sign transformers (that are not being used or are unwanted) for free. I have looked online and everyone that I have found has been way too expensive. It doesn't really matter the type, voltage, current, etc. of the transformer, I am just looking for one suitable for making a tesla coil of any size (I can adjust the design and size of the tesla coil to work well with the transformer). I would be willing to pay for shipping as long as you live in the US for I do not have very much money. Also, if you are not willing to give me or do not have a neon sign transformer, I am also looking for oil burner ignition transformers and pretty mucj any high voltage transformers that can be used for high voltage experiments/projects. If you are interested in giving me a transformer for free and are willing to pay for postage, please email me at the following email: ThatElectronicsGirl@gmail.com Otherwise, please leave a reply to this post. Whether you are willing to give me any of the transformers I asked for or not, thank you for taking the time to take a look at this post.

Posted by BeekerButts 2 years ago  |  last reply 2 years ago


Neon sign transformer

Hello everybody, I am looking for a Neon Sign Transformer (NST), I can not find any in my local area and cannot use ebay because I am 15 years old. So if anybody has an old used NST that you don't want anymore and willing to give it away or can obtain a NST for free from your local dump or neon sign stores, I would really want it! I will pay the postage bill. If you are curious why I wanted a NST, I want to build a Tesla Coil, I had built other Tesla Coils using other power supplies but I always have bad luck with them, they don't work properly so that is why I wanted a NST.I really don't mind how much voltage the NST gives out, like between 6Kv to 15Kv, but I do mind how much current it gives out, I only want a transformer that can give give out current between 20mA to 40mA, because of this, I don't want to build a big Tesla Coil yet...So, if you have a NST that you are willing to give away, please respond to me ONLY if you live in UK (United Kingdom), because I cannot afford such high postage (shipping) bill from other countries like America..

Posted by Plasmana 10 years ago  |  last reply 8 years ago


"Shunt" diodes with resistors? Answered

I'm making diode bridges to have a nice supply of DC. I'm making a high voltage bridge for a 7.5kv nst and a low voltage bridge for regular 120v wall outlet . My high voltage bridge im going to make with several 1N4007 but i read that they should be "shunted" with 10Mohm resistors im not sure what is meant by this. Does it mean resistor, diode, resistor, diode or does it mean diode and resistor, diode and resistor. The pic says it better than i do.  Also, do i need resistors for a bridge for 120v bridge?, im going to use the diodes from a fluorescent light power supply.

Asked by jaydenr 8 years ago  |  last reply 8 years ago


9kV 50mA tesla coil NST question. Why does the circuit breaker in my home trip when i plug in my NST?

Please someone help, this is my first tesla coil project, my setup: 230VAC 50Hz input ricci 9000v 50ma NST with a built in GFI (ground fault interrupter) but i bypassed the gfi succesfully .see pics safety gap  7,5 cm diameter pvc secondary 1000 turns #24 magnetwire (0,5mm) secondary 10 turns 8mm copper pipe primary (tapped at 7 turns) saltwater capacitor 16 green beer bottles in a bucket with a capacitance of 0,0122 uF or 12,2 nF (thegeekgroup bucket cap) static spark gap 28mm diameter stainless steel spheres as electrodes with oven fan (temporary, i am building a hyperbaric gap) 10cmx27,5cm aluminum toroid topload with a brass screw as breakout point RF ground aluminum rod 1,2 meter  When i tested the coil for the first time the spark gap was set on 6mm and i got 20cm or 8inch streamers without breakout point but the gfi on my nst tripped after a few seconds. i didn't know there was a built in gfi on my nst so i fooled around with my spark gap and safety gap and the tapping point on the primary hoping to get better performance. after a few runs the gfi started to trip very fast and i could only run the coil with the spark gap set on max 2mm, any bigger then that would trip the gfi on the nst. so i found out that it had a gfi and i bypassed it with thick wire. Then when i ran the nst i got the exact same thing but with my circuit breaker in my home. i have made a video on youtube that shows the problem here is the link: (please help) http://www.youtube.com/watch?v=piH44ohowyE please anyone help me! Any help or suggestion is very welkom!

Asked by colinbarnes 6 years ago  |  last reply 2 years ago


My NST is buzzing- how do I stop it?!?!?

Hello, I am in the final steps of perfecting a Tesla Coil that I started a few months back. I only got the spark gap to fire in one test run. Every other time, the circuit does nothing, and my new 10 kv neon sign transformer buzzes loudly and ominously. I'm really worried that I'll burn it out. Why is it malfunctioning? How can I fix the problem?Update: After a little experimenting, and checking all connections, I've found that the one time that the spark gap fired happened because of a wiring error (i connected the gap in series to the transformer instead of parallel); this resulted in a spark across the gap, but no oscillation. I'm starting to think that the capacitor's are the problem. I originally believed that the required capacitance was .003 uf, but I recalculated that and found that it was actually .0079 uf. This could explain why a spark couldn't jump. I'll order some more, and see how that goes. Thank you all.

Asked by ElectricUmbrella 9 years ago  |  last reply 9 years ago


What's the proper transformer for a mini tesla coil with no nst? Answered

The wire I had for the secondary coil coolness 65 feet and the primary is vertically wound around the secondary I think a neon sign trans is to high voltage maybe if I build the right cap it'll work or do you think I should do.d a smaller one. And I want it to wirelesslypower a fluorescent light also if without the best can I build the receiver take its energy useable for more electronocs

Asked by wiccakingkamui 5 years ago  |  last reply 5 years ago


Why do capacitors increase arc lengths?

I have seen a lot of videos with people increasing the arc length of a nst or mot with capacitors and i was wondering why this works. Also, is the capacitor increasing the voltage (higher potential difference, so longer arcs) or the amps (more ionisation so you can draw the arc longe)r?

Asked by makincoolstuff 7 years ago  |  last reply 2 years ago


I need help with my tesla coil! please help!

Https://www.instructables.com/answers/9kV-50mA-tesla-coil-NST-question-Why-does-the-cir/

Posted by colinbarnes 6 years ago  |  last reply 5 years ago


how to reduce current with out affecting the voltage?

I have a 12V transformer and i want to hook it up to my NST but it has a current rating of 8A but my transformer is to powerful and the lowest voltage is 12V.

Asked by Jimmy Proton 8 years ago  |  last reply 1 year ago


Can you insulate the primary coil of a Tesla coil?

Hello,    I am trying to build a tesla coil using a new design relating to a thesis paper I am working on. Due to spacial restraints my primary coil will be close to the secondary coil. I know I have seen others use insulated braided copper wire as their primary. I want to stay with 1/4" copper tubing if at all possible so I wanted to ask what affects it would have if I used heat shrink tubing on the copper tubing. I am aware the higher frequency voltage runs along the skin of the tubing since that is least resistive at that point. A for the power and caps I am using the following: three NSTs of which two are 15kv @ 30 miliamps and one 12kv @ 30 miliamps, 13 CD 2000VDC @ .15nf caps on each 15kv NST and 10 of the same caps on the 12kv NST. The spark gap is static for now.  I want to prevent arching as much as possible in the small space. Any advice is greatly appreciated. Some of the information relating to the thesis paper I cannot release due to a serious concern of being scooped before publication.  Thank you. :)

Posted by XsFacade 5 years ago  |  last reply 5 years ago


How do I make a Jacobs ladder play music?

I know theres a plasma speaker but I can't follow the plans for that I just need to know how to make an NST jacobs ladder play music I think with a 555 timer but I've never done it...?

Asked by j.hawkins 8 years ago  |  last reply 8 years ago


I want to build my first Tesla coil...need some advice about the caps

What size caps should I use in my Tesla coil...I have access to 24 and 48 uF that are used in street lights...this is my first coil and I am using a 15 kv nst..any help would be awesome

Asked by linetrician 9 years ago  |  last reply 9 years ago


Transistors in series

If I were to put transistors in series (and hook up there bases together through proper biasing resistors) would it increase the voltage capacbility of the circuit? I need a way of switching on and off about 1000 volts really fast. for example, would 2 750 volt transistors in series be able to handle 1500 volts or not? just a HV pic from my old, dead NST

Posted by guyfrom7up 10 years ago  |  last reply 10 years ago


Plasma Torch

Hello everyone, I am trying to build a plasma torch. What is a plasma torch you might ask? A plasma torch is used in a process call plasma arc gasification. I want to build a small scale working prototype for proof of concept. If anyone could help, it would be great. I can collect different MOTs or NSTs if necessary, just fill me in. Thanks for any input or direction.

Posted by axel4401 7 years ago  |  last reply 7 years ago


My problem is My MMC burn several time any suggestion?

I built a Tesla Coil,my coil's specification is 5KV NST,2inch Diameter 2ndary coil,10 turn of 4mm copper tube primary and 0.15mfd 2KV capacitor(10KV mmc with 0.030Mfd Capacitance).My MMC burn several time but the coil works fine with Leyden Jar Capacitor .Please Help me!!!!!!

Asked by Bumba Lodh 7 years ago  |  last reply 7 years ago


Is there a simple way to figure out how big of a RF choke an safety gap I need for my Tesla coil?

Ive built a pretty good sized tesla coil. Problem is, I kinda of afraid to run it without some sort of protection for my NST an my house wiring. I have three other coils of varous sizes  that Ive run without any problems, but I really dont want to push my luck. So if anyone could give me a hand on how to figure this out, I would greatly appreciate it. Many thanks in advance.

Asked by Seth the Man 7 years ago  |  last reply 7 years ago


How do I fix my tesla coil? Answered

My tesla isn't working, and I just want to see if anyone sees a problem. * NST voltage: 10,000 Volts 30 mA * 12 AWG connections wire (radio shack) * 15 feet primary copper tubing * 900 feet secondary winding * Aluminum ducking top load (18 inch diameter) * 12 0.22 uF 2000 volt capacitors (total: 12,000  volts, 0.0073 uF) * 2mm spacing spark gap * ground rod: metal knitting needle If you need more information, just ask (pictures below). Thanks for your help! (I need it to work in half a month)

Asked by Comhippy 8 years ago  |  last reply 8 years ago


Cockcroft–Walton High Voltage Power Supply

Greetings! I have wanted to begin experimenting with high voltages recently and have already collected a series of projects that I would like to conduct. The only issue is that of my high voltage power supply. I have not the funds or resources to buy into a NST or MOT system and ended up looking for alternatives. I at first tried the ignition coil route that ended in failure and have now moved on. My question is, will a Cockcroft–Walton generator be able to run say, a tesla coil, jacob's ladder, or even a farnsworth fusor given that the necessary voltage is outputted from the multiplier.  Kind of between a rock and a hard place here, Thanks anyway!

Posted by SidC1 3 years ago  |  last reply 3 years ago


need help on circuit design

Okay, I really need help on this. I want to begin a plasma speaker project, but I require help designing the circuit. I can build stuff fine, and simple high-voltage things, but complicated circuits are simply beyond my ability to design. what I am planning on doing is having a standard audio plug (l/r) feeding one circuit-probably needs to be amplified, then split into two channels, then I intend to have each channel control the driving circuit for its own neon sign transformers, as thanks to a neighbor, I will have a couple. I just need help planning out the circuit-I see how people manage plasma speakers with flybacks, but I have no idea how to make a two channel audio amplifier that splits to drive two separate control circuits that control the 110v supply that each NST takes. So, please, I beg of you, help me. and thanks in advance.

Posted by Nyanman 7 years ago


My First Tesla Coil!

I just made my first tesla coil, it stands only about 6 inches tall and has a diameter of ~1". The tank capacitence is ~940 pF. The wire gauge is 30. The topload is 6 inches in diamerer and 1 inch tall. the power supply is a 7.5kv, 60mA NST with a terry filter. It's a static spark gap. The primary has 13 turns of 14 gauge wire, it's a 30 degree cone.It gives out nice arcs and cornea. I will post photos and video soon, as my workshop reeks of ozone right now.I can probably get better preformance with using thicker (or no) aligator clips (prototype stage right now) and if I change the primary. The wire got too hard to turn, so near the center there's like 2" of leeway on all sides of the secondary... sorry about sound quality in the videothe rod in the video is kinda grounded. The rod you see is a thin copper pipe taped to a 3 foot, 1/4 inch thick dowel rod that I'm holding onto.

Posted by guyfrom7up 10 years ago  |  last reply 10 years ago


Tesla coil configuration. Audio amplifier power supply?

If I am to use an audio amplifier as a power supply for a Tesla coil could I do without a spark gap and primary capacitor? I will be operating the coil within the audible spectrum (1Hz - 20KHz) so an amplifier fits the bill. It's a 2 channel magnetic field power amplifier rated for 750W per channel. That's 750RMS not 750IFL. (If lightning strikes) The current would flow as follows: Power Amp> 4ohm Load> NST 5000v 60ma> RF Choke> Primary Coil> Secondary Coil 1. Do I need a capacitor bank between the RFC and the primary? 2. Can a few feet of 28AWG galvanized steel wire act as a reliable resistor for the 300W current? What about 750W? If not, what can I substitute? 3. Can the amp hold together? I need it in one piece. Please point out the flaws. Thank you

Asked by imMrDude 6 years ago


Can I use an ignition coil to run the primary coil of my tesla coil? Answered

Alright, I ask that everyone please read everything in this question before answering :).  I hopefully going to be very thorough.  I am building a tesla coil and am just about to give up and buy a NST.  I have many high voltage sources laying around, but, so far I haven't had much luck.  The first plan was to use a large ballast (florescent light) to drive a flyback, but it was to powerful, so I got a CFL driver, and it didn't work (not the driver so much as the whole project)  so now I am left with an ignition coil.  I know that I can use a light dimmer switch to power it, but it will still be 60hz I think and I here that is not safe for a tesla coil.  Although, I don't think anyone is going to let high frequency and voltage arc across their skin anyway.  So will something at this low of a frequency still work to power a tesla coil.  If not do you have any ideas I can use.  I have a flyback transformer and an ignition coil so any ideas that come to mind please share.

Asked by jj.inc 7 years ago  |  last reply 6 years ago


audio amplifier for singing arc speaker, 110v design

Okay, I'm planning on starting on a plasma speaker, I know somewhat how I want to build it. My neighbor has one of the old school neon sign transformers for sale, he wants next to nothing for it. So I intend to use that to simplify finding materials. I am incapable of designing a circuit, so I am asking for help. What I need is for somethng to control the 110v for the transformer based on the audio input. My alternate idea was to use two NSTs and have them become a stereo channel unit. I do prefer that idea myself. I simply have no idea how to control the sound from the arc without taking the arc out. Honestly, my electronics knowledge in circuit design made me think a really big relay would work. Until I realized that was stupid. Anyways, my preferred idea is using a project box to contain a circuit, fused around critical areas to prevent the music device being blown up on accident or anything else bad happening. A stereo plug, with one transformer being the left, the other the right. I also want to try to drive either the low voltage or the 110v computer cooling fan type things so that there is an airflow through the arc.  Please help me-I can't design circuits for the life of me, and I would rather this work out. Thanks!

Posted by Nyanman 7 years ago


Cheap and portable >12V >10A PSU for small tesla coil? any good topload sugestions?

I am currently planning a small tesla coil (15 inches high, hopefully 5-12 inch sparks) I would like to make the unit small (desktop size). I decided to build the coil around a ZVS-driven flyback transformer rather than a standard NST or Oil burner transformer due to several advantages the ZVS circuit can offer: battery operation, smaller size, simpler math, no requirement to "match" the capacitance with the transformer, and since I have almost all the parts necessary to build another ZVS driver, why not!? The ZVS driver drive a DC flyback at approximately 15KV, which will then charge a homemade capacitor (I will not invest in a true MMC because it will put stress on the capacitors and connections, not mentioning the price of better quality film capacitors.) I have determined the dielectric breakdown of a few household items (plastic wrap, lids, lunch bags, etc. I assume they are low-density polyethylene) with my ZVS singing arc assumed to be at 8-10KV, and figured one layer of 5x7 inch compressed between 8 layers of plastic wrap gives an approximate capacitance of 0.7nF (sitting flat on a table with a few books to compress the plates closer together) to 1.44nF (after being rolled up very tightly. However, the breakdown voltage of this may be too low. I have yet to test this with my singing arc project)  The Capacitor will be several layers of plastic wrap sandwiched between layers of aluminum foil, which will be cut 3/4 inch shorter on all 4 sides, and after approximately 8-15 layers have been added, the capacitor will be sandwiched between 2 wooden boards with bolts on all 4 sides to permanently compress the capacitor to achieve approximately 10nF +- 5nF. This compression method might even help me fine-tune my tesla coil!  the aluminum plates will be tabbed, so that when they are stacked, the tabs will face opposite directions.  I might even submerge the capacitor in oil and pull a vacuum on it if I feel it will be necessary. However, I have not constructed a HV capacitor before, so I do not know how well this design will work. Does anyone have some experience in this matter? And lastly, my Power supply section to power the project: Has anyone built a ZVS-based tesla coil here? I see them all over youtube, with outputs ranging from millimeters (similar to my slayer exciter project)  to over a foot long! However, they never state what their PSU is rated for, or use 12 Lead Acid batteries, which I feel would be a bit impractical. So my question is: To get the output I desire, how many volts and amps should my power supply be rated for? I am thinking either a 24V 10A Switchmode supply from amazon, with the voltage adjust maxed out, or a 28V 10.8A SMPS, or a cheaper 24V 15A. SMPS. I thought about making a unregulated supply with a large transformer and a high-amperage full-wave bridge rectifier, but this cost more, and I cant be certain on it's quality. Can SMPS be used? can the amperage be below 10A? most importantly, does anyone have good data on current draw @ given voltages @ given # of turns on the inductor and flyback?

Asked by -max- 5 years ago  |  last reply 5 years ago