Articles, Blog

Electric Fly Swatter/Zapper Racket High Voltage Power Supply

December 10, 2019

Hi Folks!
This is an electric fly swatter, or racket zapper,
made for killing flies. But it also makes for a very cheap,
though limited, high voltage power supply.
Here it’s powering a Franklin’s bell. And if you just want to make some sparks,
it does that too. You can find them in stores like Walmart,
Home Depot, Maplin and many others,
for under $8.00 or 4 euros, and also online.
This one uses two AA batteries. It has a switch on the side
that you have to hold pressed for the high voltage. Here’s a closeup of the high voltage side.
It’s made up of three meshes. An outer mesh here,
a middle one with smaller holes, and another outer one on the other side.
Here I connect to the two outer ones. When I turn it on, there’s clearly no spark.
That’s because the two outer meshes are electrically connected together.
The high voltage exists only between the outer ones and the middle one.
To prove that I wrap some non-conductive tape around most
of the end of an alligator clip. That’s so that I can clip to the middle mesh
without electrically connecting the outer mesh.
The other wire is still connected to the other outer mesh.
Either one will do. This time I get sparks. And here I’ve set up a Franklin’s bell.
In the middle of the two cans is a ball of kitchen aluminum foil.
I couldn’t get it to work with a soda can top though.
It seems to need something rounder. But there wasn’t much else I could get working
with it. There wasn’t enough current to ionize enough
air for my ion wind rotor. And also not enough current for my big corona
motor. And I know it wouldn’t work with a lifter,
or a smoke precipitator, so I didn’t even try those. Here I’ve set up my oscilloscope
and Fluke 80K-40 high voltage probe for measuring the voltage.
You can see it’s relatively low, only around 1400 volts. And finally, time to open it up and see what’s
inside. I even pry apart the racket section
to see where the wires go to the three meshes. One outer mesh is connected to the circuit
via this yellow wire, the middle mesh is connected via this red
wire, and the other outer mesh is connected via
this other yellow wire. And looking more closely at the circuit board
we can confirm that the two outer meshes are electrically connected together,
right here where the two yellow wires go to the same place. I then unscrew the circuit board.
You can see where the positive of the batteries goes to the switch
and from there to the board. While the negative of the batteries goes directly
to the board. And for those really curious,
here’s the schematic I made from analysing it.
It’s almost the same circuit as this joule thief circuit I used
to power this compact fluorescent lightbulb. There’s just an LED and current limiting resistor
added to tell when it’s turned on.
And on the output there’s a diode to turn the output into DC,
and a capacitor for smoothing. There’s also a bleed resistor,
to get rid of the high voltage when it’s turned off.
Plus another resistor right here. But other than the LED and the modification
to the output they’re both the same blocking oscillator
circuit. And that’s the electric fly swatter, or zapper
racket. Well, thanks for watching! See my youtube channel, rimstarorg for more
neat videos like this. That includes one all about the Franklin’s
bell that I demonstrated. Another on making a much more powerful
30 kilovolt high voltage power supply. And one all about my compact fluorescent lightbulb
powered by the joule thief circuit. And don’t forget to subscribe if you like
these videos, or give a thumbs up,
share with your social media, or leave a question or comment below. See you soon!


  • Reply Markus Blechschmidt February 20, 2015 at 5:43 pm

    Why is there need for DC on the grids?

  • Reply 동훈이의실험실 February 20, 2015 at 5:53 pm

    Do u have kakao Talk?

  • Reply crnazvijezda February 20, 2015 at 6:05 pm

    Hmmm, you gave me lot of ideas. Thanks!

  • Reply Fabian Peddinghaus February 20, 2015 at 6:57 pm

    Nice video as always! I guess the capacitor isnt for smoothing, but rather for storing the energy so that you dont have to constantly hold down the button.

  • Reply John Knutsson February 20, 2015 at 7:06 pm

    My experience: If you remove the bleed resistor, the voltage gets higher, but also results in an angry girlfriend who had her finger electrocuted …

  • Reply Laurentiu Jan February 20, 2015 at 7:21 pm

    Can you make a high voltage supply from a teaser? I need one to make a TEA LASER , will it work ?

  • Reply AndyFromBeaverton February 20, 2015 at 7:25 pm

    You need to modify this fly-zapper into a suet feeder with a remote control.  The purpose being to allow all birds to eat safely, but when you see a starling land on it, you can turn it on to kill/deter these flying rats.

  • Reply ‍1marcelfilms February 20, 2015 at 8:17 pm

    You should hook one of those up with a microwave capacitor its quite dangerous but fun

  • Reply Chris Pine February 20, 2015 at 9:26 pm

    very interesting!  

  • Reply BadWo1f February 20, 2015 at 11:06 pm

    I made a taser out of one. nice video.

  • Reply Laharl Krichevskoy February 20, 2015 at 11:22 pm

    Question, In the schematics it says the output cap is 400V but in the scope you show 1400. Is that normal? i've tested ceramics and electrolitics way above their nominal voltage and some seems to not have any problem despite losing capasitance (i suppose, havent actually tested that) but from 400 to 1400v seems to be a bit too high for it not to fail, more when i've seen those fail with just mains transients.

  • Reply GoRepairs February 20, 2015 at 11:44 pm

    Great explanation. I like how you came up with some creative uses for it (although zapping flies is fun).

  • Reply Slider2732 February 21, 2015 at 12:28 am

    Excellent teardown, enjoyed that. Also the comparison section to the other circuit.

  • Reply ProSurviver February 21, 2015 at 4:13 am

    Nice, I have a bunch of these laying around, the oxide layer makes amazingly huge sparks. It's good for killing and having fun lol

  • Reply JS February 21, 2015 at 5:09 am

    Can you power a CLF from it , please tell

  • Reply USWaterRockets February 21, 2015 at 5:38 am

    You need to do a video showing how to put in a transformer with a higher turns ratio to get the voltage higher!

  • Reply Todd Harrison February 21, 2015 at 6:51 am

    It would be interesting to see you mod this to power your CFL camping light. How long could the modified circuit run the hacked CFL?

  • Reply SAMIMY February 21, 2015 at 12:07 pm

    very interesting !
    i have been always wondering how these things work, nice to know now.
    by the way i have noticed a better image quality regarding to this video. what codec do you use to edit on your Sony Vegas?
    i have been going native for long time with h264, but need to replace it with something softer.

  • Reply mattibboss February 21, 2015 at 1:05 pm

    Maybe mod it add li-ion baterry and baterry charger and better high voltage circuit so it kills anything you touch?

  • Reply RimstarOrg February 21, 2015 at 5:21 pm

    Trying out an electric fly swatter as a high voltage source – and of course taking it apart to see what's inside :).

  • Reply Jenko022 February 22, 2015 at 12:42 am

    Hi Rimstar, i looked at the schematic for the zapper and i dont understand the symbol for the transformer. It looks as thought it is in two parts. What model of transformer is in the zapper? Is there a part number?

  • Reply NZHorizones February 22, 2015 at 6:54 am

    Also would like to see your results with the CFL mod please, I would like to try myself if it saves me the time finding the parts I need for the Joule Thief as I have an old model fly zapper ready to go.

  • Reply electronicsNmore February 23, 2015 at 3:28 am

    Great video! :-). You can find them at Harbor Freight as well. You can raise that 1400V with a simple multiplier circuit, but of course the current would drop.

  • Reply chris mathew February 23, 2015 at 2:12 pm


  • Reply IamIUareU February 28, 2015 at 11:54 am

    $8US or 4 euros? $8US is 7 euros here 🙁

  • Reply ‍1marcelfilms March 6, 2015 at 8:53 pm

    this video really reminds me of my early youtube days in 2009. because this

  • Reply Mark Gray March 7, 2015 at 4:38 am

    Many years ago in Channel Islands Harbor Oxnard CA I met the guy that invented this electric bug zapper. At night he would go to the light at the rest rooms where lots of bugs would be and zap them as he tested his invention. Now every time I see one of these I think of him and wonder how he is doing. I hope he is making some money off these 🙂 

  • Reply Jan March 27, 2015 at 10:19 pm

    can you put 2 or more zappers in series? to get a higher outputvoltage? or would that destroy sth like the capacitor or sth else?

  • Reply Dilemma Girl June 2, 2015 at 4:32 am

    I wanted to know if I can use a wire instead of the aligator clip?

  • Reply Amos Pressley June 22, 2015 at 2:17 am

    Good video, and well edited.

  • Reply Brandon Fisher July 26, 2015 at 3:16 pm

    Where on earth does it get the extra voltage from if the batteries themselves don't supply high voltage?????????? We all know that the extra energy (or volts) cannot simply just come out of nowhere so there must be somewhere that the 1.4 kilovolts are coming from, but like I said: little batteries like those don't supply that many volts to begin with.

  • Reply robfrmny21 August 21, 2015 at 6:22 am

    I bought one from Home Depot that uses c size batteries and claims up to 3,000 volts . Sound right ???

  • Reply Durolith September 7, 2015 at 7:06 pm

    charging 1400v in a 400v condenser =O

  • Reply Belnick6666 September 28, 2015 at 8:19 pm

    have a 50000volt tazer collecting dust, is it possible to swap them out, creating an incinerator bug swatter? 🙂

  • Reply dale nassar September 30, 2015 at 11:17 am

    Was there an actual voltage rating on the main capacitor–also was it labeled AC or DC? 1400VDc is just what I need for an app but 400V won't work,

  • Reply Richi pa October 25, 2015 at 11:32 am

    Nice one !!! can i get 12 volts dc output from it . I don't want to use the battery also…

  • Reply techdetech December 15, 2015 at 11:04 am

    nice video, well explained

  • Reply charlie jones January 25, 2016 at 12:00 am

    How many fly swatters would you require to power a corona motor

  • Reply Ed Baird April 25, 2016 at 3:49 am

    I'm trying to make a deterrent to porcupines who climb and destroy my 20+ apple trees. I've seen many mods to the racket on how to make a stun gun but I need to encompass the tree 1ft from ground with a hoop that will deliver a deterrent when activated by its weight trying to climb over it at 360 degrees. I don't know how to wire the hoop to deliver the zap on an enclosed loop?

  • Reply Home made science May 25, 2016 at 2:59 am

    Hi do you can show us how to conect 5 of that rackets and get like 12kv ? thak you for teacing us >)

  • Reply Chris Keller July 24, 2016 at 7:22 pm

    can it run a Tesla Model S ?

  • Reply ezl August 15, 2016 at 3:17 pm

    For Dogs too! 🙂 I have a dog that was being pestered by fleas that she picked up after she was outside and I have one of these
    electric flyswatters and it's hard to use to get a fly into the grid. I was wondering what it would do if it was passed over the dog?
    Well, it will really do a number on fleas since they immediately jump to objects! I would say it pretty well takes care of those pesky
    critters without bothering the dog. If you have gnats it will take care of them too. A regular flyswatter is better for flies but this thing
    is not just a novelty. Thanks for the video and information.

  • Reply Erik Buys September 8, 2016 at 8:53 am

    Liam Neeson… is that you?

  • Reply perspectivex March 8, 2017 at 8:41 pm

    Looks like you know a bit about high voltage circuits…can you recommend any resources to learn how to work with high voltage? (e.g., at home, microwave transformer/capacitor, tesla coil, etc., not high voltage power lines). I studied physics and have done a lot of low voltage electronics but don't know enough about high voltage to work safely with it.

  • Reply Dennis W March 11, 2017 at 11:01 am

    How does it output 1400V when the capacitor is only rated for 400?
    I've also been wanting to buy one of these and slightly mod the board into a driver for a GM tube, but looking at the circuit there seems to be no component that has a direct influence on the output voltage. I guess it would be better to build my own after all?

  • Reply Saahil Davey March 16, 2017 at 7:14 am

    If there are less no of electron but they are all moving with high speed does it is said to high voltage and less current

  • Reply Minhaj-Ul-Haq March 19, 2017 at 1:25 pm

    still difficult to understand. i wanna learn how to build a mosquito zipper circuit. (?)

  • Reply rilka top June 6, 2017 at 12:26 pm

    why you did not remove those battery before you disassembling that ……

  • Reply gue st June 19, 2017 at 5:55 pm


  • Reply Zimphire August 21, 2017 at 9:48 pm

    So the transformer is outputting 1,400 volts? I could use the transformer in a stun gun circuit for the T1 (first) transformer then. Wasn't sure how much voltage was coming out of that.

  • Reply Music4TheSoul September 29, 2017 at 1:40 am

    What would happen if you swapped out the two AA's with a 9v square battery?

  • Reply Music4TheSoul September 29, 2017 at 1:44 am

    I use to swap out the 3.0v Krypton Bulb in my flashlight with a 1.5v bulb, it wouldn't last as long but it was so bright you could see the beam from a long ways away.

  • Reply Terrificten October 27, 2017 at 10:05 pm

    I did that but… I spoiled the swatter

  • Reply shashi Sharma July 25, 2018 at 5:31 am

    How to make electric ion negative generator with mosquito swater circuit plzzz

  • Reply Fab Fischer December 18, 2018 at 3:01 pm

    What was the value of the capacitor? The flyswatter I took apart recently only had a cap rated for 350v. I forgot to discharge the cap once (thinking I was an electronics genius), the zap woke me right up and my throat had dilated :).

  • Reply dale nassar August 31, 2019 at 5:34 am

    Does it seem a bit odd that the output is 1400Vdc while the output cap is only 400v? THANKS FOR ALL OF YOUR GREAT VIDEOS!!!

  • Reply dale nassar August 31, 2019 at 5:37 am

    OK, I see a voltage divider at about 2:48. I don't know what the values are though.

  • Reply killmysoultray November 27, 2019 at 12:04 pm

    U so smart ??

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