{"product_id":"kit-high-speed-optical-tachometer","title":"High Speed Optical Tachometer Kit with Arduino Uno + LED","description":"\u003ch1\u003eAdvanced Optical Tachometer Kit – Precision RPM Measurement with Arduino Uno and OLED Readout\u003c\/h1\u003e\n \n\u003cp class=\"value-summary\"\u003eEvery part needed, pre-tested for compatibility, with an AI build companion trained on this exact project. Shipped from Bengaluru in 3-5 days.\u003c\/p\u003e\n \n\u003cdiv class=\"specs-strip\"\u003e\n  \u003cspan\u003e\u003cstrong\u003eDifficulty:\u003c\/strong\u003e Advanced\u003c\/span\u003e\n  \u003cspan\u003e\u003cstrong\u003eBuild Time:\u003c\/strong\u003e 5-6 hours\u003c\/span\u003e\n  \u003cspan\u003e\u003cstrong\u003eAge:\u003c\/strong\u003e 18-21\u003c\/span\u003e\n  \u003cspan\u003e\u003cstrong\u003eSkill:\u003c\/strong\u003e Non-contact sensor signal processing\u003c\/span\u003e\n\u003c\/div\u003e\n \n\u003cp\u003eWhen you're optimizing motor control loops or characterizing a high-speed BLDC prototype, trusting an encoder just isn't enough—you need a non-contact reference that can keep up. This kit equips you to build a professional-grade optical tachometer capable of reading up to 100,000 RPM using a simple strobe principle and a clean analog front-end. The IR LED\/photodiode pair captures rotor reflections, the LM393 comparator squares them into clean pulses, and the Arduino Uno counts them with 1-RPM resolution, all fed live to a crisp OLED display.\u003c\/p\u003e\n \n\u003ch2\u003eWhat You'll Build\u003c\/h2\u003e\n\u003cp\u003eYou'll assemble and calibrate a full optical RPM instrument that attaches to any motor shaft with a piece of reflective tape. The OLED will show instantaneous RPM, maximum speed, and optionally a time-log via the DS3231 RTC. Every component—from the 940nm IR emitter to the BPW34 photodiode—is included, pre-matched for consistent signal amplitude. By the end, you'll have a bench-ready tool that outperforms many handheld tachometers, all built from first principles.\u003c\/p\u003e\n \n\u003ch2\u003eWhat You'll Learn\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eDesign an optical reflection sensor with IR LED, photodiode, and ambient light filtering\u003c\/li\u003e\n  \u003cli\u003eShape noisy photocurrent into TTL pulses using an LM393 comparator with hysteresis\u003c\/li\u003e\n  \u003cli\u003eImplement an interrupt-driven RPM algorithm on Arduino Uno with overflow protection\u003c\/li\u003e\n  \u003cli\u003eInterface an I2C OLED and RTC to add persistent logging and a user-friendly display\u003c\/li\u003e\n\u003c\/ul\u003e\n \n\u003ch2\u003eKit Contents\u003c\/h2\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eComponent\u003c\/th\u003e\n\u003cth\u003eQuantity\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eArduino Uno R3\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eIR LED 940nm\u003c\/td\u003e\n\u003ctd\u003e2\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eBPW34 Photodiode\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eLM393 Comparator\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eDS3231 RTC\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e0.96in OLED\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e220Ω Resistors\u003c\/td\u003e\n\u003ctd\u003e5\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e10kΩ Resistors\u003c\/td\u003e\n\u003ctd\u003e10\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e100nF Caps\u003c\/td\u003e\n\u003ctd\u003e10\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003ePCB Prototype Board\u003c\/td\u003e\n\u003ctd\u003e2\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e9V Battery Snap\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eSoldering Iron\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eSolder Wire\u003c\/td\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n \n\u003ch2\u003eWhy Buy This Kit Instead of Sourcing Parts Separately\u003c\/h2\u003e\n\u003ctable\u003e\n  \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eFactor\u003c\/th\u003e\n\u003cth\u003eSourcing Separately\u003c\/th\u003e\n\u003cth\u003eCompoden Kit\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003eCompatibility checks\u003c\/td\u003e\n\u003ctd\u003eYou verify every part\u003c\/td\u003e\n\u003ctd\u003ePre-tested as a system\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eBuild support\u003c\/td\u003e\n\u003ctd\u003eForums and scattered tutorials\u003c\/td\u003e\n\u003ctd\u003eAI companion trained on this exact project\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eTime to first working build\u003c\/td\u003e\n\u003ctd\u003eDays of debugging\u003c\/td\u003e\n\u003ctd\u003eHours, with step-by-step guidance\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003eShipping coordination\u003c\/td\u003e\n\u003ctd\u003eMultiple sellers, multiple delays\u003c\/td\u003e\n\u003ctd\u003eOne shipment from Bengaluru in 3-5 days\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n \n\u003ch2\u003eWho This Kit Is For\u003c\/h2\u003e\n\u003cp\u003eThis advanced kit targets B.Tech ECE\/EEE students working on motor drive characterization, Smart India Hackathon teams that need a reliable RPM readout, and IIT\/NIT\/VIT\/BITS Pilani participants building FOC algorithms or high-speed spindle projects. CBSE Class 11-12 students comfortable with Arduino and basic analog electronics will also find it challenging, but the AI companion walks through every calculation. ATL Tinkering Lab mentors can use it as a capstone instrumentation project.\u003c\/p\u003e\n \n\u003ch2\u003eBuilt and Backed by Compoden\u003c\/h2\u003e\n\u003cp\u003eEvery Compoden kit ships with an AI build companion trained on this exact project — accessible via a QR code on the box, with WhatsApp and email backup. We've spent 10 years building projects for makers, schools, and institutions across India. If a part fails because of a manufacturing defect, replace it free within 7 days.\u003c\/p\u003e\n \n\u003cdetails\u003e\u003csummary\u003eWhat if I get stuck during the build?\u003c\/summary\u003e\u003cp\u003eYour QR code unlocks a companion that has seen this exact oscilloscope trace and knows every step. If you're still blocked, message us on WhatsApp and we'll help within hours.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eCan I measure RPM without making physical contact with the motor?\u003c\/summary\u003e\u003cp\u003eYes—stick a small piece of reflective tape on the rotating part. The IR beam bounces into the sensor, generating one pulse per revolution entirely without friction.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWill the readings stay accurate at low speeds, like 50 RPM?\u003c\/summary\u003e\u003cp\u003eAt low RPM the Arduino's interrupt timing remains precise, but you'll need a clean reflection. We've included a 100nF capacitor filter to suppress spurious transitions at slow edges.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eI have a 3D printer enclosure; can I mount the sensor remotely?\u003c\/summary\u003e\u003cp\u003eThe BPW34 has a decent field of view. You can extend the LED and photodiode on wires from the comparator board, letting you position the head near a window in the enclosure.\u003c\/p\u003e\u003c\/details\u003e\n\n\u003cdiv class=\"kit-description\"\u003e\n  \u003cp\u003eIR LED and photodiode strobe measures RPM of spinning motors up to 100,000 RPM. OLED shows live speed.\u003c\/p\u003e\n  \u003ch4\u003eWhat's in this kit\u003c\/h4\u003e\n  \u003cul\u003e\n    \u003cli\u003e\u003ca href=\"\/products\/uno-r3-ch340g-atmega328p-board-arduino-compatible\"\u003eArduino Uno R3\u003c\/a\u003e\u003c\/li\u003e\n    \u003cli\u003e\n\u003ca href=\"\/products\/9-in-1-arduino-sensor-kit-with-ultrasonic-pir-dht11-mq2-more\"\u003eIR LED 940nm\u003c\/a\u003e x2\u003c\/li\u003e\n    \u003cli\u003eBPW34 Photodiode\u003c\/li\u003e\n    \u003cli\u003e\u003ca href=\"\/products\/lm393-motor-speed-sensor-module-for-arduino-rpm-measurement\"\u003eLM393 Comparator\u003c\/a\u003e\u003c\/li\u003e\n    \u003cli\u003e\u003ca href=\"\/products\/ds3231-real-time-clock-module-i2c-rtc-with-battery-backup\"\u003eDS3231 RTC\u003c\/a\u003e\u003c\/li\u003e\n    \u003cli\u003e\u003ca href=\"\/products\/096in-oled-display-128x64-i2cspi-for-arduino-raspberry-pi\"\u003e0.96in OLED\u003c\/a\u003e\u003c\/li\u003e\n    \u003cli\u003e\n\u003ca href=\"\/products\/resistor-variety-pack-100-pcs-10-values-14w-carbon-film\"\u003e220Ω Resistors\u003c\/a\u003e x5\u003c\/li\u003e\n    \u003cli\u003e\n\u003ca href=\"\/products\/resistor-variety-pack-100-pcs-10-values-14w-carbon-film\"\u003e10kΩ Resistors\u003c\/a\u003e x10\u003c\/li\u003e\n    \u003cli\u003e\n\u003ca href=\"\/products\/capacitor-variety-pack-6-values-100nf-to-470uf-30-pieces\"\u003e100nF Caps\u003c\/a\u003e x10\u003c\/li\u003e\n    \u003cli\u003e\n\u003ca href=\"\/products\/esp-wroom-32-breakout-board-pcb-55x52mm\"\u003ePCB Prototype Board\u003c\/a\u003e x2\u003c\/li\u003e\n    \u003cli\u003e\u003ca href=\"\/products\/9v-battery-snap-connector-with-15cm-wires-compoden\"\u003e9V Battery Snap\u003c\/a\u003e\u003c\/li\u003e\n    \u003cli\u003e\u003ca href=\"\/products\/soldering-kit-25w-with-solder-wire-flux-paste-compoden\"\u003eSoldering Iron\u003c\/a\u003e\u003c\/li\u003e\n    \u003cli\u003e\u003ca href=\"\/products\/soldering-kit-25w-with-solder-wire-flux-paste-compoden\"\u003eSolder Wire\u003c\/a\u003e\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/div\u003e\n\n\u003cscript type=\"application\/ld+json\"\u003e\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"FAQPage\",\n  \"mainEntity\": [\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What is included in the High Speed Optical Tachometer Kit with Arduino Uno + LED?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"The High Speed Optical Tachometer Kit with Arduino Uno + LED includes all components needed: Arduino Uno R3, IR LED 940nm, BPW34 Photodiode, LM393 Comparator, DS3231 RTC and more. Everything is pre-tested for compatibility and shipped from Bengaluru, India.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What skill level is required for the High Speed Optical Tachometer Kit with Arduino Uno + LED?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"This kit is designed for Advanced level makers, suitable for ages 18-21. IR LED and photodiode strobe measures RPM of spinning motors up to 100,000 RPM. OLED shows live speed. Estimated build time is 5-6 hrs.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Can I buy the High Speed Optical Tachometer Kit with Arduino Uno + LED online in India?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Yes, the High Speed Optical Tachometer Kit with Arduino Uno + LED is available online at Compoden (compoden.in), India's AI-powered electronics and robotics store. Ships from Bengaluru in 1-5 business days across India.\"\n      }\n    }\n  ]\n}\n\u003c\/script\u003e\n\n\u003cscript type=\"application\/ld+json\"\u003e\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"Product\",\n  \"name\": \"High Speed Optical Tachometer Kit with Arduino Uno + LED\",\n  \"description\": \"IR LED and photodiode strobe measures RPM of spinning motors up to 100,000 RPM. OLED shows live speed.\",\n  \"sku\": \"CDN-KIT-1192\",\n  \"brand\": {\"@type\": \"Brand\", \"name\": \"Compoden\"},\n  \"offers\": {\n    \"@type\": \"Offer\",\n    \"url\": \"https:\/\/compoden.in\/products\/kit-high-speed-optical-tachometer\",\n    \"priceCurrency\": \"INR\",\n    \"price\": \"3260\",\n    \"availability\": \"https:\/\/schema.org\/InStock\",\n    \"seller\": {\"@type\": \"Organization\", \"name\": \"Compoden\"}\n  },\n  \"category\": \"Sensor Starter Kits\"\n}\n\u003c\/script\u003e\u003cp\u003e\u003cstrong\u003eChoose your assembly option:\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSoldering Kit\u003c\/strong\u003e — 25W soldering iron, 60\/40 solder wire, flux, and small perfboard for permanent assembly.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBreadboard Combo\u003c\/strong\u003e — 800-point full-size breadboard with 65-piece jumper wire pack for solderless prototyping.\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Compoden","offers":[{"title":"Clone \/ Soldering Kit","offer_id":53456504521069,"sku":"CDN-KIT-1192-CL-SLD","price":2470.0,"currency_code":"INR","in_stock":true},{"title":"Clone \/ Breadboard Combo","offer_id":53459831816557,"sku":"CDN-KIT-1192-CL-BB","price":1940.0,"currency_code":"INR","in_stock":true},{"title":"R3 Original \/ Soldering Kit","offer_id":53456504553837,"sku":"CDN-KIT-1192-R3-SLD","price":4900.0,"currency_code":"INR","in_stock":true},{"title":"R3 Original \/ Breadboard Combo","offer_id":53459831849325,"sku":"CDN-KIT-1192-R3-BB","price":4370.0,"currency_code":"INR","in_stock":true},{"title":"R4 WiFi \/ Soldering Kit","offer_id":53456504586605,"sku":"CDN-KIT-1192-R4-SLD","price":4220.0,"currency_code":"INR","in_stock":true},{"title":"R4 WiFi \/ Breadboard Combo","offer_id":53459831882093,"sku":"CDN-KIT-1192-R4-BB","price":3690.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0999\/3997\/5533\/files\/kit-high-speed-optical-tachometer.png?v=1781946487","url":"https:\/\/compoden.com\/products\/kit-high-speed-optical-tachometer","provider":"Compoden","version":"1.0","type":"link"}