Pi Pico Hall Effect Tachometer
Pi Pico Hall Effect Tachometer Kit — Build a Compact RPM Diagnostic Tool
Every part needed, pre-tested for compatibility, with an AI build companion trained on this exact project. Shipped from Bengaluru in 3-5 days.
Ever wondered exactly how fast a DC motor, fan, or drone propeller spins? This kit transforms a Raspberry Pi Pico and an A3144 Hall effect sensor into a real‑time digital tachometer. Just attach a small magnet to any rotating shaft, hold the sensor nearby, and watch the live RPM on the crisp 0.96‑inch OLED display — a pocket‑sized diagnostic tool you can use anywhere.
What You'll Build
You’ll solder and assemble a standalone RPM meter housed in a sturdy ABS enclosure. Once running, you clip the Hall sensor close to a spinning magnetic rotor — the Pico counts pulses, calculates speed, and updates the OLED every few milliseconds. The result is a compact, battery‑friendly device that helps you test motors for robotics, tune propeller speeds, or simply satisfy your curiosity about how fast things rotate.
What You'll Learn
- How a Hall effect sensor detects magnetic fields and converts them into clean electrical pulses
- Programming the Raspberry Pi Pico in MicroPython to handle interrupts and compute RPM accurately
- Driving a 0.96‑inch OLED over I2C to display live sensor data
- Through‑hole soldering, PCB prototyping, and assembling a finished project in an enclosure
Kit Contents
| Component | Quantity |
|---|---|
| Raspberry Pi Pico | 1 |
| A3144 Hall Sensor | 1 |
| 0.96in OLED | 1 |
| 10kΩ Resistors | 5 |
| PCB Prototype Board | 2 |
| ABS Enclosure Box | 1 |
| Micro USB Cable | 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 hits the sweet spot for CBSE Class 5–12 students exploring rotational motion, ATL Tinkering Lab mentors running sensor workshops, and B.Tech ECE/EEE first‑years needing a quick mini‑project. Young hobbyists aged 8 and up (with adult help for soldering) will love seeing their code turn into a real‑world instrument. It’s also used in Smart India Hackathon hardware tracks for rapid motor prototyping.
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?
Scan the QR code on the box to talk to the AI build companion, or message us on WhatsApp. We’ll walk you through step‑by‑step using this exact kit’s components.
Do I need a separate magnet to measure RPM?
Yes, any small neodymium disc magnet (not included) attached to the motor shaft will work. The Hall sensor detects its passing, generating the pulses the Pico counts.
Is the kit safe for a 10‑year‑old?
All parts are low‑voltage and RoHS compliant, but soldering is required. Adult supervision is recommended for builders under 12. The final device runs safely on USB power.
What RPM range can it measure?
The A3144 sensor and Pi Pico software can reliably measure from a few hundred to over 10,000 RPM, as long as the magnet is placed close to the sensor. The code includes debounce filtering for stable readings even at high speeds.
A3144 hall sensor and Pi Pico measure motor RPM. OLED shows live speed. Compact diagnostic tool.
What's in this kit
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