Luyện nói tiếng Anh bằng Shadowing qua video: I Made an EMP Device... It Actually Works

Imagine instead of using wires to transfer electricity wirelessly on one side I give a 5 volts to a  coil creating a field around it and the second coil picks up that field and turns it back to  into power. You can see this exact system in wireless phone charger. What what if instead of  5 volts I feed thousands or millions of volts into the coil and instead of a second coil I  place a phone a calculator a camera it could be any other electronic device as you know all  these device are made of circuits and wires they can pick up that field with this much voltage we  can fry all of them engineers call it an EMP or electromagnetic pulse and in this video I'm going  to build one first of all This EMP device needs a really high voltage generator. So I decided  to make a custom transformer. I found this FR core and took some measurements. Then I designed  a layered cylinder around it. I printed it on my Formlabs printer using clear resin. I really love  this printer. It's super precise. And finally, I got this clear print. For the secondary coil,  I used a 0.1 mm coated wire. To keep track of the turns, I used this tally counter, but instead  of pressing the physical button, I took it out and soldered the red switch in its place. Now I  can count the turns just by spinning a magnet.

For the first section, I was really careful  and won 800 turns because if the wire breaks, I have to start all over again.  After finishing the first 800 turns, I moved the wire to the next section  and did another 800 turns and then again and again. Anyway, after a lot  of neck pain and eating bunch of candy, I repeat this process 15 times. Done. totally  12,000 turns, but I haven't insulated yet.

To insulate the transformer, I use epoxy  resin, but I didn't go with the usual 1:22 ratio. I actually used less hardener. It takes  longer to cure this way, but it completely coats all the wires. I also put it in a vacuum  chamber to remove all the tiny air bubbles.

And for the primary coil, I want nine turns using  thick wire. And that's it. Now I have 12,000 secondary turns and nine primary turns. That  means whatever voltage I put into the transformer, I'll get 1,333 times at the output. For  the flyback circuit, I use a super simple setup with just the MOSFET and the PWM module.  Basically, the measure generates the signal at whatever frequency I set and sends it to the  MOSFET gate to boost it. I powered the circuit with a 9V power supply and hook it the output  to the transformer. I tuned the frequency to 12.5 KHz with a 70% duty cycle. You have to find  these exact numbers track and error and they are unique to every transformer, but generally  it sits somewhere between 10 and 25 kHz.

I love electronics again. Again.

Yes. Me and electricity. We are basically  married couple now. For all the circuits, I designed and 3D printed the case. I swapped  the old MOSFET heat sink for bigger one. To control the transformer, I added a switch right  between the MOSFET gate and the PWM signal. Also, for the power source, I used an 8V  battery pack with a charging port.

So far, I've built a high voltage generator, but honestly, that's not enough to create a real EMP  pulse. I actually need to something that can store all this energy and in a split second boom release  it all. So I'm going to need a capacitor and marks generator circuit. But what is exactly marks  generator? Imagine I have a big power source and six batteries. First I charge them in a parallel  and after the full charge I disconnect them. Now each batteries is charged up to the exact voltage  of the power source. For the output, I connect them together in series. Instead, now my output is  exactly six times the original voltage. Since we are getting closer to actually generating the EM  pulse, I covered my camera in aluminum foil like a mini farat cage to protect it from the pulse. And  speaking of protection, as you guys know, for this project, I downloaded a massive amount of data,  3D file, and code every single day. The reality is any of those could easily be interfected with  malware. Luckily, the sponsor of today's video, NordVPN, completely solve this security issue for  me. A lot of people think a VPN just for changing your IP address, but it's way more than that. All  those files I download could hide malware that might wipe up my project or compromise my privacy.  But NorVPN thread protection feature acts as an invisible shield. It scans and filters the files  before they even reach my system. On top of that, when I'm researching new builds, I constantly  run into resources that are geoblocked or restricted in my region. With NordVPN, I have  access to thousands of servers worldwide.

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And if you're not totally convinced yet, don't  worry because they offer a 30-day money back guarantee. All right, let's back to the project.  Now, instead of batteries, I'm using these 15 kW nanopharad capacitors. Also, to get even more  power, I soldered them together in series.

But instead of just one, yeah, I need eight  of them. I line them up to next to each other and use these resistors to build the parallel  path I want. If your electronics are solid, let me know in the comments why I put  these resistors between the capacitors.

The parallel path is ready. But you can't have a  parallel and the series connection at the exact same time. But Mark uses a really clever  trick. Instead of using solid wires between the capacitors for the series path, he uses the  spark gaps. So now the transformer charges the capacitor in parallel and the moment they are  fully charged, they unleash their energy as a spark. And that's exactly what creates our series  pass between these two pins. Let's test it. Okay.

Yeah, I think I know why it's not working. A mark  circuit actually work with DC voltage while my transformer outputs AC. Luckily, solving this is  the easiest part of the whole project. I just used these high voltage diodes to build a rectifier  and added this straight into the circuit.

Can you see these sparks? They are exactly what  creates that series path I was talking about.

To finish it up, I packet the entire circuit  inside the case, leaving only the two high voltage outputs sticking out. Now, the only thing  is left winding the coil to actually generate the pulse. But there are a few crucial details here.  First off, the shape of the coil itself. Usually, everyone wind these in a standard cylindrical  car shape, but I found something way better, the pancake coil. I actually analyzed the  magnetic field for both. With a cylindrical coil, a large part of wave just stays trapped inside the  cylinder. But with a pancake coil, the pause is literally shot straight forward. The second point  is I only want the pass to travel in one direction along the coil. You talk it naturally generates  in a both directions. Well, I actually found the solution in this wireless charging module.  Specifically, this shield behind the coil. Look at this. Right now, the pass is focused on one  side to charge the phone. But if I flip it over, the pass actually can't pass through the metal.  And that's exactly the point. Metals block the false. So, keeping all these points in my mind,  I finally added these piece to it. A pancake coil with a metal shield right behind it. And for the  first test, I tried it out on my digital caliper.

Well, I've always hate math, so I think  it's time to destroy this one, too.

Beautiful. Don't worry.

Next up is this, my lovely Apple  Watch. It's worked perfectly and it's in a great condition, but it's a fake.

Next up is my old monitor. It works  perfectly, but just for you guys.

See you in the next video. Bye-bye.