Crystal Frequency Tester Kit: Identify Fake Crystals with Arduino Uno and OLED

Every part needed, pre-tested for compatibility, with an AI build companion trained on this exact project. Shipped from Bengaluru in 3-5 days.

Counterfeit crystals are a silent menace—mislabeled 12MHz as 16MHz, salvaged parts sold as new, or dead units that won't oscillate at all. In India, such components often slip into project bins and anonymous orders, causing hours of fruitless debugging. This kit gives you a dedicated instrument that inserts any crystal into a 74HC14 Schmitt-trigger oscillator, measures the actual frequency with Arduino-calculated precision, and compares it against the nominal value, so you'll know within seconds whether your clock source is genuine, off-tolerance, or fake. No more trusting markings; build your own crystal verifier and save every project from hidden timing faults.

What You'll Build

You'll construct a battery-powered frequency tester on a prototype PCB, complete with a crystal socket for effortless swapping. After uploading the pre-written sketch, drop in an unknown crystal, and the 0.96-inch OLED display reads out the measured frequency in hertz, the percentage deviation from the marked value, and a clear verdict: GENUINE, OFF-TOLERANCE, or NO OSCILLATION. It's a compact, portable tool that lives on your workbench, ready to check every quartz you salvage, purchase, or doubt.

What You'll Learn

• Build a stable clock oscillator using a 74HC14 inverter and understand load capacitance selection
• Convert the oscillator output into a clean digital signal for Arduino frequency counting, using DS3231's temperature-compensated reference for high accuracy
• Program an interrupt-driven frequency counter that handles prescaling for crystals up to 20MHz
• Read out results on a 0.96-inch OLED and implement pass/fail logic based on percentage tolerance thresholds

Kit Contents

Why Buy This Kit Instead of Sourcing Parts Separately

Who This Kit Is For

This kit is tailored for CBSE Class 11-12 physics and computer science students exploring digital electronics, B.Tech ECE/EEE undergraduates who need a reliable crystal checker for lab projects, and Smart India Hackathon teams that must quickly verify salvaged or donated parts during prototyping. ATL Tinkering Lab instructors will find it a rich hands-on module on oscillators and frequency measurement, while independent makers gain a permanent diagnostics tool for their bench.

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.