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Signal build

How to transfer Music through Light

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

Radio & soundBuildOpticsAudio

Watch on YouTube

How it works

What this project is testing.

Sound does not have to travel as pressure waves in air. In this project, music is turned into tiny changes in a light beam, sent across space, and then turned back into an electrical signal.

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The experiment demonstrates optical communication in a very visible way: the beam is the carrier, the music is the modulation, and alignment matters because the receiver only hears what the light sensor can see.

I (t) = I_{0} + k s (t)

The brightness of the light can be varied around a steady level by the audio signal.

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.

Jesverty DC Power Supply Variable, 0-30V 0-10A Adjustable Switching DC Regulated Bench Power Supply with High Precision 4-Dig

bench DC power supplypower

Variable DC Bench Power Supply, 30V 10A Adjustable Regulated Supply

$64.994.5(2,700)

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.

Rigol Digital Oscilloscope DS1054Z 50 MHz 4-Ch 1 GSa/s 24 Mpts 30,000 wfms/s UltraVision 7" 800x480 Intensity Display, 60,000-Frame Record/Playback, Serial Decode UART I2C SPI for Debug & Education

oscilloscopetest equipment

Rigol DS1054Z Digital Oscilloscope, 50 MHz, 4 Channel, 1 GSa/s

$349.004.7(724)

Good bench choice; budget scope alternatives may be cheaper but less durable.

Goupchn Universal P6100 Oscilloscope Clip Probes 100MHz with Accessories Kit 1X 10X 2 Pack

test probes / leadstest equipment

Goupchn Universal P6100 Oscilloscope Clip Probes, 100MHz, 1X/10X, 2 Pack

$13.994.7(126)

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)

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)

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 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)

150 Pcs 15 Value 100 ohm- 2M ohm Trimpot Variable Resistor 6mm Potentiometer Assortment Kit

potentiometerpassive electronics

150 Pcs 15-Value 100 ohm-2M ohm Trimpot Variable Resistor Potentiometer Assortment Kit

$11.994.6(267)

CQRobot Speaker 3 Watt 8 Ohm Compatible with Arduino Motherboard, JST-PH2.0 Interface. It is Ideal for a Variety of Small Electronic Projects.

speakeraudio

CQRobot 3 Watt 8 Ohm Speaker for Arduino and Small Electronics Projects

$7.994.5(457)

Syncwire 3.5mm Nylon Braided Aux Cable (3.3ft/1m,Hi-Fi Sound), Audio Auxiliary Input Adapter Male to Male Cord for Headphones, Car, Home Stereos, Speaker, iPhone, iPad, iPod, Echo & More – Black

audio source / phoneaudio

3.5mm Nylon Braided Aux Cable, Male to Male, 3.3ft

$7.994.6(119K)

Use with an existing phone or audio player.

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)

WOWOONE Laser Diode 30Pcs 5V 650nm 5mW Mini Red Dot Laser Head, 6mm Outer Diameter Laser Module with Leads, for Arduino Laser DIY Electronics Projects, High-Stability Red Laser Diode

laser / laser pointeroptics

30pcs 5V 650nm 5mW Mini Red Dot Laser Diode Modules with Leads

$12.994.6(152)

Laser safety matters. Keep recommendations to low-power modules and add eye-safety warnings. Review requirements and safety guidance before buying.

SUNYIMA 10pcs Mini Monocrystalline Solar Cells Solar System Kit 50mm X 50mm/1.96" X 1.96" 2V 160MA for DIY Charge Solar Panels

solar cell / photovoltaic panelpower

SUNYIMA 10pcs Mini Monocrystalline Solar Cells, 50mm x 50mm, 2V 160mA

$15.994.5(284)

RUEHALF Front Surface Mirrors, 100 * 100 * 3mm First 1st Surface Mirror,Surface Mirror Optics Quality for Engineering and Scientific Project

mirroroptics

Front Surface Mirror, 100 x 100 x 3mm, First Surface Optics Quality Mirror

$19.04

For interferometer/optics use, prefer first-surface mirrors over bathroom/craft mirrors. Amazon review evidence is sparse. Review requirements and safety guidance before buying.

Optical Glass Cube Dichroic Beam Splitter Prism Ratio 50:50 Spectrome Sicence 15X15X15MM

beam splitteroptics

Optical Glass Cube Dichroic Beam Splitter Prism, 50:50, 15x15x15mm

$13.994.8(17)

Specialty optics have fewer Amazon reviews; verify size and wavelength before publishing. Review requirements and safety guidance before buying.

$Physics Optical Experiment Set Multifunction Reflector Refraction Triangular Prism Convex Lens Concave Mirror Dial Linear Light Source Teaching Demonstration Equipment for Teacher Student Education$

lensoptics

Physics Optical Experiment Set with Prism, Convex Lens, Concave Mirror, and Linear Light Source

$18.994.3(198)

Specialty optics may need size and focal-length review before publishing.

5PCS 3.3V-5V Photodiode Module LM393 Light Sensor Switch Module for Arduino Raspberry Pi Photosensitive Diode Detection Switch

photodetector / photodiodesensor

5PCS 3.3V-5V Photodiode Module LM393 Light Sensor Switch Module

$7.995.0(4)

Good functional match for a photodiode module, but it has sparse Amazon review evidence. Review requirements and safety guidance before buying.

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)

HiLetgo Mini 3W+3W DC 5V Audio Amplifier Handy Digital Power Amp Module Board Dual-Channel PAM8403 Stereo Amplifiers with Potentiometer for DIY Portable

audio amplifier moduleaudio

HiLetgo Mini 3W+3W DC 5V Audio Amplifier Handy Digital Power Amp Module Board Dual-Channel PAM8403 Stereo Amplifiers with Potentiometer for DIY Portable

$5.194.4(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

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