Digital Tachometer Laser Kit with Arduino Uno + LED
Digital Laser Tachometer Kit with Arduino Uno — Measure RPM of Any Rotating Shaft
Every part needed, pre-tested for compatibility, with an AI build companion trained on this exact project. Shipped from Bengaluru in 3-5 days.
You will build a precise non-contact tachometer that measures the rotational speed of motors, fans, lathes, and wheels. A low‑power laser beams onto a reflective marker on the shaft, and a BPW34 photodiode picks up each reflected pulse. The Arduino Uno processes the signal and instantly displays RPM on a crisp 0.96‑inch OLED screen — perfect for tuning machinery, science projects, or industrial prototyping.
What You'll Build
You will construct a handheld digital tachometer that reads RPM from 60 to over 10,000 with high accuracy. The device uses a self‑contained laser‑photodiode sensor unit and an OLED readout. It measures any rotating object once a piece of reflective tape is attached — no physical contact needed, making it safe and precise.
What You'll Learn
- How a photodiode and laser work together for non‑contact object detection
- Signal conditioning using an LM393 comparator to convert photodiode pulses into clean digital signals
- Arduino programming for frequency measurement and RPM calculation
- Soldering and assembling a functional PCB prototype board
Kit Contents
| Component | Quantity |
|---|---|
| Arduino Uno R3 | 1 |
| 5mW Laser Module | 1 |
| BPW34 Photodiode | 1 |
| LM393 Comparator | 1 |
| 0.96in OLED Display | 1 |
| 220Ω Resistors | 5 |
| 10kΩ Resistors | 5 |
| 100nF Ceramic Capacitors | 5 |
| PCB Prototype Board | 2 |
| 9V Battery Snap | 1 |
| Soldering Iron | 1 |
| Solder Wire | 1 |
Why Buy This Kit Instead of Sourcing Parts Separately
| Factor | Sourcing Separately | Compoden Kit |
|---|---|---|
| Compatibility checks | You verify every part | Pre-tested as a system |
| Build support | Forums and scattered tutorials | AI companion trained on this exact project |
| Time to first working build | Days of debugging | Hours, with step-by-step guidance |
| Shipping coordination | Multiple sellers, multiple delays | One shipment from Bengaluru in 3-5 days |
Who This Kit Is For
This kit is ideal for CBSE Class 11–12 students working on physics or electronics projects, first‑year B.Tech ECE/EEE undergraduates, and participants in the Smart India Hackathon building mechanical measurement tools. ATL Tinkering Labs and colleges like VIT, NIT, or BITS will find it a ready‑made instrumentation module.
Built and Backed by Compoden
Every 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.
What if I get stuck during the build?
Our AI build companion, accessed via QR code, gives step‑by‑step guidance, and you can reach us on WhatsApp for human backup.
Can I measure RPM of a motor without reflective tape?
Reflective tape is required for the laser to detect a pulse. Any shiny tape works; we recommend standard retro‑reflective tape (not included).
Does this work on outdoor machinery in sunlight?
The photodiode sensor is sensitive to ambient light. For outdoor use, shade the sensor or use it indoors. The laser pulse is strong enough for most indoor environments.
Can I power it from a USB instead of 9V battery?
The Arduino Uno can be powered via USB while programming, but for portable measurements, the 9V battery is recommended. You can also use a 9V DC adapter.
Laser + photodiode measures RPM of any spinning shaft by counting reflective tape passes. OLED shows RPM.
What's in this kit
- Arduino Uno R3
- 5mW Laser Module
- BPW34 Photodiode
- LM393 Comparator
- 0.96in OLED
- 220Ω Resistors x5
- 10kΩ Resistors x5
- 100nF Caps x5
- PCB Prototype Board x2
- 9V Battery Snap
- Soldering Iron
- Solder Wire
Choose your assembly option:
- Soldering Kit — 25W soldering iron, 60/40 solder wire, flux, and small perfboard for permanent assembly.
- Breadboard Combo — 800-point full-size breadboard with 65-piece jumper wire pack for solderless prototyping.
Other projects you can build
Shipping Information
- Prepaid Orders: ₹75 for orders up to ₹999, FREE shipping above ₹999
- COD Orders: ₹125 shipping + ₹50 COD fee = ₹175 total
- Delivery Timeline: Dispatch in 1-2 days, delivery in 2-7 days depending on location
Returns & Warranty
- 7-Day Return: Manufacturing defects only (approval required)
- Warranty: 7 days from delivery
- Non-Returnable: Batteries, consumables, cut wires, clearance items