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High-voltage build

electric timer from a microwave

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

High voltageBuild

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How it works

What this project is testing.

A microwave timer turns time into a switching action. Depending on the design, that timing can come from a clocked controller, a synchronous motor, or a simple charge-and-threshold delay.

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The experiment demonstrates that a timer is not mysterious: it is a measured process that eventually flips a switch, relay, or control signal after a predictable interval.

τ = R C

For simple resistor-capacitor timing stages, this time constant sets how quickly voltage changes.

n_{s} = \frac{120 f}{p}

For synchronous AC motors, speed is tied to line frequency and motor pole count.

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.

Auto Ranging Digital Multimeter TRMS 6000 with Battery Alligator Clips Test Leads AC/DC Voltage/Account,Voltage Alert, Amp/Ohm/Volt Multi Tester/Diode

multimetertest equipment

Auto-Ranging Digital Multimeter TRMS 6000 with Battery, Alligator Clips, and Test Leads

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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

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YIHUA 926 III 60W Digital Display Soldering Iron Station Kit

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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)

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)

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

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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)

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

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

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

SYCZIOHU Universal Microwave Oven High Voltage Capacitor 2100V 1.05 MFD uF Household Microwave Replacement Part

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Universal Microwave Oven High Voltage Capacitor, 1.05 MFD

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High-voltage capacitors retain dangerous charge. Recommend only with clear safety language. Review requirements and safety guidance before buying.

NoCry Clear Safety Glasses for Men and Women with Anti-Fog and Scratch Resistant Wrap Around Lenses, Adjustable Temples and Nose Pads — ANSI Z87 Certified Protective Eyewear with 100% UV Shielding

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NoCry Clear Safety Glasses with Anti-Fog and Scratch-Resistant Wraparound Lenses, ANSI Z87 Certified

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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

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 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 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)

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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