Tesla coils and other high voltage equipment that make sparks are always entertaining and potentially dangerous. There are some portable tesla coils you can buy online that say, “safe, low current”, and yet they still produce lightning and have a high voltage output.700K Mini Coil Tube Neon Glow Coil With Transparent Plate Power Supply For Tesla is one such device I tested. Here is some story about it.
Let’s start with basics:The Tesla coil is an electrical resonant transformer circuit designed by inventor Nikola Tesla in 1891. It is used to produce high-voltage, low-current, high frequency alternating-current electricity.Ever since Tesla’s 1890s lectures, Tesla coils have been used as attractions in educational exhibits and science fairs. They have become a way to counter the stereotype that science is boring. They are old, but I this they are still cool!
700K Mini Coil Tube Neon Glow Coil With Transparent Plate Power Supply For Tesla page promised following technical specifications:
Color: As the picture shows
Power supply: 220V / 110V AC
About 700k frequency
“arc can be touched by hand”
“Can light of incandescent lamp, energy-saving lamps, integrating scientific demonstration and entertainment, suitable as a magic props used in science and education, science and technology museum and school exhibits, etc.”
Package includes:
1 x Tesla’s Coil
1 x Adaptor
7 x Small accessories
The coil is around 100 mm long. So the device is quite small. The product I recieved looked somewhat different than on the product page picture showed, but the most important details were OK. Here is picture of the coil I received:
The electronics is pretty simple: One power transistor, few passives and the Tesla secondary coil:
The circuit is powered with mains power supply that gives out 9V 1A DC to the electronics:
The Tesla coil driver circuit is based on a version of quite popular Slayer Exciter Circuit. Electroboom article Slayer Exciter Circuit with a Tesla Coil has explanation (circuit diagram, text and video) how the circuit works. Here is circuti diagram from that page:
On my700K Mini Coil Tube Neon Glow Coil With Transparent Plate Power Supply For Tesla it seems that the diode is a LED – and some other slight modifications. The transistor circuit makes the secondary coil to oscillate as long as it gets proper feedback from the secondary coil (through capactance to ground). The circuit keeps oscillating on normal condtions, but in case the secondary gets shorted the or loaded too much., the oscillation stops – a good safety feature: coil turns off if you accidentally touch it (also protects electronics against overload).
Some maybe interesting measured data: The Tesla coil secondary on this unit I have has resistance fo aroun 55 ohms and inductance of around 370 microhenry. I would have wanted to measure the current consumption of he Tesla coil on use, but the cheap multimeter I tried to use for that failed to work properly near the Tesla coil (maybe it did not like the high electric field and/or high frequency pulsating current).
Here is the device prepared to make sparks. I added the yeallow wire to the device. It is connected to the output coil end that is connected to transistor base. I use that wire to make nice sparks.
The original documentation talks about 700 kHz operating frequency (if I undersand that 700k frequency right). The real frequency seems to be something quite different according to my oscilloscope: around 3.5 MHz. This was measured with normal oscilloscope probe aroudn 30 cm away from the coil on the table (I did not want to put it near the high voltage source that can damage my oscilloscope).
Many Tesla coils have some capacitive load on the top. Here is my attempt to add some capacitance on the top: piece of plastic wapped on aluminium foil. It chamges frequency.
The Tesla coil can in this configuration light up the supplied neon bulbs from some distance nicely. It can also make sparks (quite small compared to bigger Tesla coils). Neon indicator lamps are normally orange, but this package also had special green version also included.
Ggg
700K Mini Coil Tube Neon Glow Coil With Transparent Plate Power Supply For Tesla is cheap ($10) and quite funny high voltage device to play with. It might not be the most useful tool on electronics lab and does not make huge sparks (I woudl have wanted mych biggr sparks!), but it is still fun. Look at the following web pages for ideas what kind of experiments can be done with Tesla coils (some experiments ask for much bigger coil):
http://www.instructables.com/id/Tesla-coil-experiments/
http://www.techeblog.com/index.php/tech-gadget/7-cool-and-creative-tesla-coil-experiments
NOTE: Besides high voltage electrical field generation Tesla coil can be a big source of radio frequency interference. Keep the Tesla coil away from any sensitive electronics devices!
49 Comments
Tomi Engdahl says:
I was wondering on number of turns.
With following tools
http://www.daycounter.com/Calculators/Air-Core-Inductor-Calculator.phtml and
https://m0ukd.com/calculators/air-cored-inductor-calculator/
I got result that number of turns on Tesla coil secondary would have around 300 turns.
Sounds reasonable number to me.
Tomi Engdahl says:
Strange results on coil impedance:
Another meter gave 1.3 mH and 53 ohms.
I used this meter
http://www.epanorama.net/newepa/2014/08/18/diy-electronics-tester-kit-m168/
Tomi Engdahl says:
PCB Tesla Coil Is Perfect Desk Toy
https://hackaday.com/2017/10/30/pcb-tesla-coil-is-perfect-desk-toy/
A Tesla coil easily makes it to the top spot on our list of “Mad Scientist” equipment we want for the lab, second only to maybe a Jacob’s Ladder. Even then, it’s kind of unfair advantage because you know people only want a Jacob’s Ladder for that awesome sound it makes. Sound effects not withstanding, it’s Tesla coil all the way, no question.
Unfortunately, winding your own Tesla coil is kind of a hassle. Even on relatively small builds, you’ll generally need to setup some kind of winding jig just to do the secondary coil, which can be a project in itself. So when [Daniel Eindhoven] sent his no-wind Tesla coil into the tip line, it immediately got our attention.
The genius in his design is that the coils are actually etched into the PCB, completely taking the human effort out of the equation. Made up of 6 mil traces with 6 mil separation, the PCB coil manages to pack a 25 meter long, 160 turn coil into an incredibly compact package. As you might expect, such a tiny Tesla coil isn’t exactly going to be a powerhouse, and in fact [Daniel] has managed to get the entirely thing running on the 500 mA output of your standard USB 2.0 port.
PCB TeslaCoil, USB powered
http://www.megavolts.nl/en/projects/tesla-coils/201-pcb-spiral-teslacoil-en
Tomi Engdahl says:
Low-End Parts Make Tesla Coil with a High-End Look
https://hackaday.com/2017/11/25/low-end-parts-make-tesla-coil-with-a-high-end-look/
We all know the saying: cheap, fast, or good — pick any two. That rule seems to apply across the spectrum of hackerdom, from software projects to hardware builds. But this DIY Tesla coil build might just manage to deliver on all three.
DIY 3 volt tesla coil MUSEUM QUALITY
https://www.youtube.com/watch?v=zbV1zyg_4qU
Tomi Engdahl says:
How to Make a Tesla Coil. Experiments with High Voltage
https://www.youtube.com/watch?v=33nv5sErrY4
A Tesla Coil with a battery of 15 volts and also interesting effects with high voltage.
http://anod7.ru/files/tesla-coil-scheme.png
Tomi Engdahl says:
The Tesla coil circuit is quite similar to ones used in plasma balls:
USB plasma ball teardown and schematic.
https://www.youtube.com/watch?v=TbKUlLdEQqo
USB plasma ball. Once you see that it radiates a very high voltage gradient at high frequency you may choose not to plug it into, or place it near anything expensive….
It’s really nice to see that the circuitry inside has not changed from the original units from many decades ago.
If you like high voltage electronics and plasma then this thing is worth buying just for the PCB inside. It’s very hard to wind reliable high voltage, high frequency transformers like the one used here, so it’s worth every penny just for that little flyback transformer.
Tomi Engdahl says:
Make a mini “Tesla coil” (Easy to make)
https://www.youtube.com/watch?v=MjTK-L3sLxI
*)BATTERY
*)On/Off SWITCH
*)TRANSISTOR 2n 2222A
*)22K RESISTANCE
*)20ml SYRINGE
*)27NUMBER COPPER WIRE
Tomi Engdahl says:
Musical Tesla Coil Kit
https://www.youtube.com/watch?v=GdhTVwSygqo
demonstrate an ebay mini ‘slayer exciter’ Tesla coil kit that features a music input.
Tomi Engdahl says:
DIY Tesla Slayer Exciter Coil Tutorial Mini How to Build Easy Circuit Explanation
https://www.youtube.com/watch?v=mRTAoy257QE
Tomi Engdahl says:
Easy Tesla Coil
https://www.eeweb.com/featured-projects/easy-tesla-coil
Easy Tesla Coil project features a wireless transmission of electricity. It is a wireless power transfer project that is achievable with few materials and some basic electronic components. This project uses MJE3055T NPN transistor for its switching control instead of high voltage spark gap.
This project is comprised few materials in which for the primary coil uses a short 2.5” PVC pipe and a 16 ga. insulated copper wire is winded or a three rotations evenly spaced about ¼” apart of this insulated copper wire on the 2.5” PVC pipe. While for the secondary coil and transmitter cap, a magnet wire is winded straight on a 2″ PVC pipe with a specific 1/4″ space between the winded part and both ends of the PVC pipe.
Tomi Engdahl says:
DIY 3 volt tesla coil MUSEUM QUALITY
https://www.youtube.com/watch?v=zbV1zyg_4qU
Feel like Tesla himself! Learn how to build a high quality table top tesla coil, powered by a mere 3 volts, and a bit of elbow grease. We’re talking two AA batteries. From scratch to finish, this is your one stop tutorial on building your first tesla coil. These things stand less than 6″ tall, and are built to last. 3v into 30,000? Lets do this.
Tomi Engdahl says:
Make a mini “Tesla coil” (Easy to make)
https://www.youtube.com/watch?v=MjTK-L3sLxI
*)BATTERY *)On/Off SWITCH *)TRANSISTOR 2n 2222A *)22K RESISTANCE *)20ml SYRINGE *)27NUMBER COPPER WIRE
Tomi Engdahl says:
Musical Tesla Coil Kit
https://www.youtube.com/watch?v=GdhTVwSygqo
In this video I build and demonstrate an ebay mini ‘slayer exciter’ Tesla coil kit that features a music input.
Tomi Engdahl says:
How to make a mini Tesla coil
https://www.youtube.com/watch?v=3zjnX41K1pE
In this video we learn how to make a tesla coil with 9 volt battery
Tomi Engdahl says:
https://hackaday.com/2019/04/25/a-tesla-coil-from-pcbs/
Tomi Engdahl says:
A Tesla Coil From PCBs
https://hackaday.com/2019/04/25/a-tesla-coil-from-pcbs/
The limiting factor on Tesla coils comes from the abilities of a transistor to efficiently switch at higher frequencies. Few designs make it above the tens of kHz switching frequencies, and thus they rely on the large coils we’re used to. A PCB coil can not practically have enough inductance for these lower frequencies, thus Niklas’ design employs a very high frequency indeed for a Tesla coil design, 2.6 MHz with both primary and secondary coils being resonant.
Tomi Engdahl says:
360 tour of The University of Manchester’s High Voltage Lab
https://www.youtube.com/watch?v=yBedWO5cRF0
Hear Dr Vidyadhar Peesapati explain the work that goes on inside the UK’s largest ‘lightning lab’.
http://www.mub.eps.manchester.ac.uk/science-engineering/2017/04/10/drone-vs-lightning/
Tomi Engdahl says:
These PCB-Based Tesla Coils Can Be Controlled via MIDI
https://blog.hackster.io/these-pcb-based-tesla-coils-can-be-controlled-via-midi-641de7f8fa9f
Tomi Engdahl says:
https://www.eeweb.com/profile/calimero22/articles/how-to-design-a-tesla-coil?utm_source=newsletter&utm_campaign=link&utm_medium=EEWebEngInsp-20191212
Tomi Engdahl says:
Music, Magic and Mayhem with Tesla Coil
https://www.youtube.com/watch?v=L5E4NiP4hpM
I love what you can achieve with a Tesla coil! There are too many details, all talked about in the article in my website. Did you know you can play clear music with electrons?!
http://www.electroboom.com/?p=575
Tomi Engdahl says:
ElectroVLOG-004: The LAST Attempt at Tesla in Vacuum
https://www.youtube.com/watch?v=gb0kyRm0gyc
Tomi Engdahl says:
Reverse engineering an electrical spark igniter
https://www.edn.com/reverse-engineering-an-electrical-spark-igniter/
Tomi Engdahl says:
Compact Slayer Exciter For Your High Voltage Needs
https://hackaday.com/2020/03/21/compact-slayer-exciter-for-your-high-voltage-needs/
Tomi Engdahl says:
A 555 And A Lighter Make High Voltage
https://hackaday.com/2020/03/19/a-555-and-a-lighter-make-high-voltage/
Tomi Engdahl says:
https://www.newservice.xyz/2020/07/neon-lamp-circuits-working-or.html?m=1
Tomi Engdahl says:
DIY simple 220v one transistor Tesla Coil
https://m.youtube.com/watch?v=Q1M2VBvOzLA&feature=youtu.be
Julkaistu 18.7.2020
A Tesla coil is an electrical resonant transformer circuit designed by inventor Nikola Tesla in 1891. It is used to produce high-voltage, low-current, high frequency alternating-current electricity.
The video describes how to make a Tesla coil with the help of only a few components:
– Fluorescent lamp ballast (one or two , 370mA-740mA)
– UF5408 or similar ultrafast diode
– 1 microF/400v MKP capacitor
– IRFP250 or similar Mosfet Transistor
– 12v/1w Zener diodes – 2pcs
– Potentiometer 10 kOhm
– 12 kOhm 1/2w resistor
– coils (primary and secundary)
Characteristic of this design is that it does not use expensive elements like transformers and capacitors, it is easy to make and produces a relatively large spark of 5 cm and more.
You can dowbnload schematic diagram at:
https://snipboard.io/lK5I7s.jpg
And a very important note: The device is powered directly on 200V so you must adhere to all safety rules
Tomi Engdahl says:
Video of bigger Tesla Coil
https://www.facebook.com/groups/765877716770273/permalink/3327417033949649/
Tomi Engdahl says:
Covid coil
https://www.facebook.com/groups/765877716770273/permalink/3327417033949649/
Tomi Engdahl says:
Demostration with bigger and more powerful tesla
https://www.facebook.com/groups/electronichobycircuits/permalink/3550033041688046/
https://www.instagram.com/mohammed_haj_hammod/?hl=en
Tomi Engdahl says:
https://hackaday.com/2020/09/09/tesla-coil-electric-bikes-is-wireless/
Tomi Engdahl says:
https://hackaday.com/2017/11/25/low-end-parts-make-tesla-coil-with-a-high-end-look/
Tomi Engdahl says:
Extremly simple Tesla Coil with only 3 Passive components (8+ cm spark) at 220V AC
https://www.youtube.com/watch?v=uQAuy7lBAlo
This is certainly the simplest Tesla Coil that can ever work. It is so simple that it can be made by anyone who has the most basic knowledge in the field of electrical engineering. And most importantly, the cost of the parts needed to make it is minimal.
Tomi Engdahl says:
https://www.iflscience.com/editors-blog/build-your-own-singing-tesla-coil-with-this-cool-diy-kit/
Tomi Engdahl says:
https://hackaday.com/2021/02/01/electric-candle-replaces-flame-with-plasma/
Tomi Engdahl says:
The World’s Hottest Candle Can Actually Melt Steel—Plasma Candle
https://www.youtube.com/watch?v=3vtGktz8c1M
In this video I show you a plasma candle made from an ultra high frequency solid state tesla coil (HFSSTC). I talk about why it was tripping the breakers in my house and show you how hot these plasma candles actually are. I talk about why the color of the “flame” is white vs blue or violet.
Everybody: uses candle because of a power breakdown.
The Action Lab: has a power breakdown because of using a candle.
his house: constantly trying to protect itself from burning down
him: unacceptable
Building a Wireless Power Plasma Candle ( Flame Discharge ft. Teslaundmehr)
https://www.youtube.com/watch?v=SyZuel2iaBk
Imagine a candle that never runs out of wax. One which transmits wireless power, and burns hot enough to instantly melt metal. A plasma flame, which is controlled by a dial. It would be nice if something like that existed. Well, now it does. As a collaboration between Plasma Channel and Leon at Teslaundamehr, this project was one of my favorite builds to date. NOTE: My location is RF shielded, and all precautions were taken to eliminate local RF interference (though, with flame lit, RF interference is near zero).
Tomi Engdahl says:
https://www.facebook.com/groups/electronichobycircuits/permalink/4360613073963368/
DIY Plasma Tweeter (HF SSTC)
Plasma Speaker made with the help of semiconductors,
specifically high power Mosfet transistors.
Instructions and schematic at: https://youtu.be/NGzH2gtGhZQ
Tomi Engdahl says:
A Builders Guide For The Perfect Solid-State Tesla Coil
https://hackaday.com/2021/10/31/a-builders-guide-for-the-perfect-solid-state-tesla-coil/
[Zach Armstrong] presents for your viewing pleasure a simple guide to building a solid-state Tesla coil. The design is based around a self-resonant setup using the UCC2742x gate driver IC, which is used in a transformer-coupled full-wave configuration for delivering maximum power from the line input. The self-resonant bit is implemented by using a small antenna nearby the coil to pick up the EM field, and by suitably clamping and squaring it up, it is fed back into the gate driver to close the feedback loop. Such a setup within reason allows the circuit to oscillate with a wide range of Tesla coil designs, and track any small changes, minimizing the need for fiddly manual tuning that is the usual path you follow building these things.
The Easy, Powerful Solid State Tesla Coil
https://hackaday.io/project/182391-the-easy-powerful-solid-state-tesla-coil
An easy, half-bridge SSTC that can produce beautiful, 12″ sparks with only a few watts of input power
Tomi Engdahl says:
Mini Tabletop Tesla Coil Powered by an Arc Lighter
Rechargeable Portable Spark Gap Tesla Coil for Science Demonstrations
https://hackaday.io/project/182677-mini-tabletop-tesla-coil-powered-by-an-arc-lighter
This coil was inspired by a build by Jay over at the Plasma Channel on YouTube https://youtu.be/4GRyxuRIPPo
I began this adventure while attempting to rebuild a tabletop spark gap Tesla coil I previously used in demonstrations at some Maker Faire’s. That coil was a basic spark gap coil using a 12 volt power supply, a television fly-back coil driven by a ZVS circuit and hand rolled high voltage capacitors. My primary goal was to make a small and safe (table top sized) spark gap Tesla Coil with an integral and rechargeable power supply to use for demonstrations at a local science museum as well as in classrooms at local schools.
Tomi Engdahl says:
Making a Tesla Coil Magic Wand, to Celebrate 5 MILLION SUBS!
https://www.youtube.com/watch?v=sXJg9J81acY
Tomi Engdahl says:
https://hackaday.com/2022/03/18/high-tech-pancake-tesla-coil-brings-the-lightning/
Tomi Engdahl says:
Building the World’s Simplest QCW DRSSTC
https://hackaday.io/project/184038-building-the-worlds-simplest-qcw-drsstc
QCW Tesla coils have been something of a complex mystery since their creation…until now!
The QCW DRSSTC: some consider it to be the crown-achievement of the amateur high voltage community. A magnificent and extremely rare device capable of producing electrical sparks much larger than the device itself. Since its creation, the QCW Tesla coil has remained something of a mystery…until NOW!
In this article, you will not only discover how a traditional QCW coils operates, but also learn how to properly build and construct your very own staccato-based QCW Tesla coil. This particular design is easier, cheaper, and quieter than most Tesla coil designs, and it’s safe enough for indoor use. To top it all off, when this thing is built right, it can produce sparks over FOUR TIMES the length of the coil itself! So what are you waiting for? Let’s build!
For more information, be sure to check out my official video tutorial: https://www.youtube.com/watch?v=MWlDGUHWMXw
Tomi Engdahl says:
Junkbox Build Keeps Tesla Coils Perfectly Varnished
https://hackaday.com/2022/08/09/junkbox-build-keeps-tesla-coils-perfectly-varnished/
Admittedly, not a lot of people have a regular need to varnish coils. It’s mainly something that Tesla coil builders and other high-voltage experimenters are concerned with. But since that group probably constitutes a not insignificant fraction of the Hackaday audience, and because there are probably more applications for this homebrew coil varnishing setup, we figured it would be a good idea to share it.
How To Varnish A Tesla Coil Secondary Coil
https://www.youtube.com/watch?v=iLT4hfC793U
Tomi Engdahl says:
Mini Tabletop Tesla Coil Powered by an Arc Lighter
Rechargeable Portable Spark Gap Tesla Coil for Science Demonstrations
https://hackaday.io/project/182677-mini-tabletop-tesla-coil-powered-by-an-arc-lighter
This coil was inspired by a build by Jay over at the Plasma Channel on YouTube https://youtu.be/4GRyxuRIPPo
I began this adventure while attempting to rebuild a tabletop spark gap Tesla coil I previously used in demonstrations at some Maker Faire’s. That coil was a basic spark gap coil using a 12 volt power supply, a television fly-back coil driven by a ZVS circuit and hand rolled high voltage capacitors. My primary goal was to make a small and safe (table top sized) spark gap Tesla Coil with an integral and rechargeable power supply to use for demonstrations at a local science museum as well as in classrooms at local schools.
Since I achieved my primary goal, my new goal is to provide the information for anyone to build a similar coil, including how to change design parameters based on what resources they have available.
I will be posting links to all files and resources used to build this Mini Tabletop Tesla Coil Powered by an Arc Lighter.
Tomi Engdahl says:
Mini Tabletop Tesla Coil Powered by an Arc Lighter
https://hackaday.io/project/182677-mini-tabletop-tesla-coil-powered-by-an-arc-lighter
Rechargeable Portable Spark Gap Tesla Coil for Science Demonstrations
Tomi Engdahl says:
https://hackaday.com/2023/02/11/playing-music-on-a-custom-flyback-transformer/
Tomi Engdahl says:
A Tesla coil with only three components!
https://www.youtube.com/watch?v=HHsG_dBZyCM
A simplified version of the Slayer Exciter solid state Tesla coil using only a 10F supercapacitor, a 2N3904 npn transistor and an 85 turn coil.
It requires an electromagnetic pulse to start resonating at very high frequency.
The larger model uses a 2N2222 transistor.
Tomi Engdahl says:
https://hackaday.com/2023/06/27/build-a-tesla-coil-with-just-three-components/
Tomi Engdahl says:
https://hackaday.com/2024/04/26/build-your-own-class-e-musical-tesla-coil/
Tomi Engdahl says:
Tesla coil tuning
https://youtu.be/zVVySjt-JNs?si=dV1deD6nRPDaX59r