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Signal build

Pocket 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 magical because your hand changes the instrument without touching it. Nearby objects change capacitance, nudging an oscillator frequency until that change becomes an audible pitch.

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The pocket version makes the same principle small: a sensor, an oscillator, and your hand form a changing field that the circuit turns into sound.

f \approx \frac{1}{2 π L C}

Many simple oscillators change pitch when capacitance or inductance changes.

C \propto \frac{A}{d}

Capacitance rises as conductive surfaces get closer together.

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.

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 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 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)

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)

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)

XINGYHENG 175pcs 7Values 5mm Photoresistor Optoresistor Photo Light Sensitive Resistor Assortment Kit (GL5506 /GL5516 /GL5526 /GL5528 /GL5537 /GM5539 /GL5549) (LDR Photo Resistors Light-dependen)

photoresistor / LDRsensor

XINGYHENG 175pcs Photoresistor Assortment Kit

$11.994.6(184)

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

relay / switchcontrol

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

$5.694.6(381)

LeMotech IP67 Waterproof Junction Box ABS Plastic Project Box Dustproof Electrical Box Outdoor Enclosure for Electronics DIY Case Gray 9.8X 3.1x 3.3 inch (250x 80x 85 mm)

project enclosurefabrication

LeMotech ABS Plastic Project Box Electronics Enclosure

$16.994.6(1,153)

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.

Glarks 122Pcs 2.54mm Pitch 6 8 14 16 18 24 28 40 Pin DIP IC Sockets Solder Type Adaptor Assortment Kit

IC socketprototyping

Glarks 122pcs DIP IC Sockets Assortment Kit

$11.994.5(516)

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

Events, speaking, collaborations, and news.

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