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Electricity

Remote Switch

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

ElectricityBuild

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How it works

What this project is testing.

A remote switch is really a small signal making a bigger decision somewhere else. The interesting part is the handoff: detect a command, cross a threshold, then change the state of a load.

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This project demonstrates control logic, switching, and why separating a signal path from a power path is useful in electronics.

P = I V

A switch may be controlled by a small signal while the load itself can use much more power.

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)

BOJACK 14 Value 240 pcs Diode Assortment Kit Contain Rectifier/Fast Recovery/Schottky/Switching Diode 1N4001 1N4004 1N4007 1N5404 1N5406 1N5408 RL207 FR107 FR207 UF4007 1N5817 1N5819 1N5822 1N4148

diodesemiconductor

BOJACK 14-Value 240pcs Diode Assortment Kit

4.8(1,000)

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)

BOJACK 20 Values 200 Pcs Inductor 10 uH to 10 mH 1 W Color Ring Inductor 1 Watt Assortment Kit

inductor / coilpassive electronics

20 Values 200 Pcs Inductor Assortment Kit, 1uH to 4.7mH, 0.5W Color Ring Inductors

$13.994.8(182)

12V 2A Power Supply, AC 120V to DC12V 5.5x2.1mm Jack Converter, 12 Volt LED Driver 24W Adapter Transformer for Strip Lights, Surveillance Cameras, External HDD, Monitor, CCTV (Pack of 1)

transformerpower

12V 2A Power Supply, AC 120V to DC12V 5.5x2.1mm Adapter Transformer

$8.994.5(6,601)

General low-voltage transformer/adapter pick; match voltage/current and connector to the circuit.

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)

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.

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

microwave ovensalvage

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

$148.994.4(32K)

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

12V 2A Power Supply, AC 120V to DC12V 5.5x2.1mm Jack Converter, 12 Volt LED Driver 24W Adapter Transformer for Strip Lights, Surveillance Cameras, External HDD, Monitor, CCTV (Pack of 1)

wall adapter / DC adapterpower

12V 2A Power Supply, AC 120V to DC12V 5.5x2.1mm Jack Converter, 12 Volt LED Driver 24W Adapter Transformer

$8.994.5(6,601)

General 12V wall adapter pick; match voltage/current, polarity, and connector to the circuit.

IR remote controlcontrol

Universal-TV-Remote-Control Compatible with Samsung/LG/Vizio/Hisense/Sony/Philips/Onn/Sharp/RCA/Element/Westinghouse/Sanyo/Emerson TV and More Brand Smart TVs

$9.974.5(64K)

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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