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High-voltage build

5$ taser!

Start with the video, then use the science notes and recommended parts below to follow the idea behind the build.

High voltageBuild

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How it works

What this project is testing.

The useful science here is the high-voltage discharge, not copying a dangerous device. This project demonstrates charge storage, electric-field breakdown through air, and why stored energy matters.

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A big voltage number by itself is not the whole story. The risk changes with stored energy, current path, insulation, and how easily the discharge can cross a gap.

U = \frac{1}{2} C V^{2}

Stored energy in a capacitor rises with the square of voltage.

V_{b r e ak d o w n} \approx E_{b r e ak d o w n} d

Air sparks when the electric field across a gap becomes large enough.

Recommended parts

Products used in this project.

Affiliate links may earn Keystone Science a commission. Match ratings, values, sizes, polarity, and safety requirements to your own build before buying.

Amazon Basics 8-Pack 9V Long-Lasting Alkaline Batteries for Smoke Detector, Electronics & Audio, Reliable, 5-Year Shelf Life

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General electronics battery pick; choose AA/AAA variants when the circuit calls for them.

YIHUA 926 III 60W Digital Display Soldering Iron Station Kit w 2 Helping Hands, 6 Extra Iron Tips, Lead-Free Solder, Solder Sucker, S/S Tweezers, °C/ºF Conversion, Auto Sleep & Calibration Support

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Tolako 5v Relay Module 5V Indicator Light LED 1 Channel Relay Module for Arduino ARM PIC AVR MCU

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5V 1-Channel Relay Module with Indicator LED for Arduino, ARM, PIC, AVR, and MCU Projects

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Eastman 0.17 Inch ID (1/4 Inch OD) PVC Clear Vinyl Tubing, 20 Foot Length, 98560

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Eastman Clear Vinyl Tubing, 0.17 Inch ID, 1/4 Inch OD, 20 Foot Length

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TOSHIBA EM131A5C-BS Countertop Microwave Ovens 1.2 Cu Ft, 12.4" Removable Turntable Smart Humidity Sensor 12 Auto Menus Mute Function ECO Mode Easy Clean Interior Black Color 1000W

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Toshiba EM131A5C-BS Countertop Microwave Oven, 1.2 Cu Ft, 1000W

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Recommend only as an appliance; do not encourage buying a working microwave for disassembly. Review requirements and safety guidance before buying.

NoCry Clear Safety Glasses for Men and Women with Anti-Fog and Scratch Resistant Wrap Around Lenses, Adjustable Temples and Nose Pads — ANSI Z87 Certified Protective Eyewear with 100% UV Shielding

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NoCry Clear Safety Glasses with Anti-Fog and Scratch-Resistant Wraparound Lenses, ANSI Z87 Certified

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Lead-Free Solder Wire Rosin Core Flux 0.8mm Electric Solder Fine Sn99 Ag0.3 Cu0.7 Flow 0.032in 0.11lb No Lead for Electronics Soldering Unlead 50g

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Lead-Free Rosin Core Solder Wire

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CHANZON UL Wires 20PACK 9v Battery Dual Connector Clip UL Wires I Type Snap with Pigtail Housing Soft Leather Leads Wires for Adapter Replacement Terminal

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Gorilla Mini Hot Glue Gun Kit (Pack of 1 Mini Hot Glue Gun and 30 Sticks) - Dual Temp, Precision Nozzle, and Easy Squeeze Trigger

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Gorilla Mini Hot Glue Gun Kit with Glue Sticks

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3M Scotch Vinyl Electrical Tape Super 88, 3/4 in x 44 ft, Black, 1 roll, Premium Grade, Rubber Resin Adhesive, PVC Backing, A

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3M Scotch Super 33+ Vinyl Electrical Tape

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Eventronic 600PCS Heat Shrink Tubing 2:1, Electrical Wire Cable Wrap Assortment Electric Insulation Heat Shrink Tube Kit with Box(5 colors/12 Sizes), Black, Red, Blue, Yellow, Green

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Eventronic Heat Shrink Tubing Kit, 560 Pieces

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Project files

Prints, kits, and downloads.

Diagrams, printable files, kits, or companion downloads will appear here when they are ready to use.

Coming soon

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