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Signal build

Theremin

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

Radio & soundBuildAudio

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How it works

What this project is testing.

A theremin feels like magic because you play it without touching it. Your hand changes the electric field around an antenna, which slightly changes an oscillator frequency.

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The experiment demonstrates capacitance, oscillation, and beat frequencies: tiny field changes become pitch changes your ear can hear.

f = \frac{1}{2 π L C}

The resonant frequency shifts when the effective capacitance changes.

f_{b e a t} = ∣ f_{1} - f_{2} ∣

Two nearby oscillator frequencies can mix into an audible difference tone.

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

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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.

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

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

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

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

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

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

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

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

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

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E-outstanding 1 Pair AM FM Radio Universal Antenna, 62.5cm 24.6" Length 4 Section Telescopic Stainless Steel Replacement Antenna Aerial for Radio TV

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Ackers High Borosilicate Glass Measuring Cup Set with Pour Spout,60ml(2OZ),120ml(4OZ), 250ml(8OZ) Glass Measuring Beaker for Kitchen or Restaurant, Easy to Read

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Reynolds Wrap Everyday Strength Aluminum Foil Roll, Freezer and Grill Safe, Great for Foil Packets and Home Cooking, 12 Inches Wide, 200 Total Sq. Ft.

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

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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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