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Electricity

How to make Running LEDs

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

ElectricityBuildElectronics

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How it works

What this project is testing.

Running LEDs create motion from timing. Each light is simple, but turning them on in sequence makes your eye read the pattern as movement.

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The experiment demonstrates clock pulses, sequencing, timing speed, and persistence of vision.

f = \frac{1}{T}

The step rate is the inverse of the time between steps.

τ = R C

In many timer-style circuits, resistance and capacitance set how quickly the timing changes.

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.

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

soldering ironfabrication

YIHUA 926 III 60W Digital Display Soldering Iron Station Kit

$39.994.4(6,900)

BOJACK 3 Values 130 Pcs Solderless Breadboard 4 Pcs 830 Tie Points & 400 Tie Points & 126 Pcs Flexible Breadboard Jumper Wires

breadboardprototyping

BOJACK Solderless Breadboard Kit with 830/400 Tie-Point Boards and Flexible Jumper Wires

$9.994.4(692)

EDGELEC 120pcs Breadboard Jumper Wires 20cm Wire Length Optional Dupont Cable Assorted Kit Male to Female Multicolored Ribbon Cables

jumper wires / hookup wirewiring

120pcs Breadboard Jumper Wires, 20cm Dupont Cable Assorted Kit, Male to Female

$6.984.7(4,500)

BOJACK 1000 Pcs 25 Values Resistor Kit 1 Ohm-1M Ohm with 5% 1/4W Carbon Film Resistors Assortment

resistorpassive electronics

BOJACK 1000 Pcs 25-Value 1/4W Carbon Film Resistor Assortment Kit, 1 ohm-1M ohm

$9.994.7(4,500)

BOJACK 24Value 630pcs Aluminum Electrolytic Capacitor Assortment Box Kit Range 0.1uF－1000uF

capacitorpassive electronics

BOJACK 24-Value 630pcs Aluminum Electrolytic Capacitor Assortment Box Kit, 0.1uF-1000uF

$16.994.7(953)

CHANZON 100pcs 5mm LED Diode Lights Assortment 10 Colors x 10pcs Diodes (Clear Transparent Lens) Emitting Lighting Bulb Lamp Assorted Kit Variety Color White Red Yellow Green Blue Orange UV Pink

LEDsemiconductor

100pcs 5mm LED Diode Lights Assortment, 10 Colors

$6.994.5(1,800)

BOJACK 10 Values 250 Pcs A1015 BC327 BC337 C1815 S8050 S8550 2N2222 2N2907 2N3904 2N3906 PNP NPN Power General Purpose Transistors Assortment Kit

transistor / MOSFETsemiconductor

BOJACK 10-Value 250 Pcs PNP/NPN General Purpose Transistor Assortment Kit

$8.994.7(763)

BOJACK 12 Values 120 Pcs Opamp Timer Darlington Phototcoupler LM324 LM339 ULN2003AN ULN2803APG LM358P LM386 LM393 NE5532P NE555P UA741CN JRC4558D PC817 IC Assortment Kit

integrated circuit / ICsemiconductor

BOJACK 12 Values 120 Pcs Opamp Timer Darlington Phototcoupler LM324 LM339 ULN2003AN ULN2803APG LM358P LM386 LM393 NE5532P NE555P UA741CN JRC4558D PC817 IC Assortment Kit

$18.994.8(511)

Panasonic Portable AM/FM Radio, Battery Operated Analog Radio, AC Powered, Silver (RF-2400D)

AM/FM radio receiverradio

Panasonic RF-2400D Portable AM/FM Radio, Battery Operated or AC Powered

$29.994.5(33K)

Pure Life Distilled Water 2.5 Gallon, 320 Fl Oz

waterfluid

Pure Life Distilled Water, 2.5 Gallon

$5.694.6(410)

2 x 13.5 Pounds Arm & Hammer Pure Baking Soda (27 Pounds Total)

salt / electrolytechemistry

Arm & Hammer Pure Baking Soda, 2 x 13.5 Pounds

4.8(1,100)

For electrolysis demos, baking soda is often a safer electrolyte than table salt.

Apple 2025 MacBook Pro Laptop with Apple M5 chip with 10‑core CPU and 10‑core GPU: Built for AI, 14.2-inch Liquid Retina XDR Display, 16GB Unified Memory, 1TB SSD Storage; Space Black

computercomputing

Apple 2025 MacBook Pro Laptop with Apple M5 chip with 10-core CPU and 10-core GPU: Built for AI, 14.2-inch Liquid Retina XDR Display, 16GB Unified Memory, 1TB SSD Storage; Space Black

$1,538.304.7(107)

Preferred Apple laptop option for coding, editing, and project-control work.

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

batterypower

Amazon Basics 8-Pack 9V Long-Lasting Alkaline Batteries

$12.694.7(242K)

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

ElectroCookie Large PCB Prototype Board Kit Solderable Breadboards for Electronics Projects Compatible for DIY Arduino Soldering Projects, Gold-Plated (6 Multi-Pack, Blue)

printed circuit board / PCBprototyping

ElectroCookie Large PCB Prototype Board Kit, Solderable Breadboards for Electronics Projects

4.8(111)

Project files

Prints, kits, and downloads.

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

Coming soon

Contact

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