Acoustic Rain Gauge Kit: Solar-Powered Raindrop Size Distribution with Arduino Mega

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

Imagine deploying a weather station that doesn’t just count rain — it classifies every drop by size using sound. This kit lets you build a self-contained acoustic rain gauge that listens to raindrop impacts on a metal plate through a sensitive microphone, then processes the pitch to output real-time size distribution. With solar power and waterproof housing, you get a field-ready instrument that replaces costly disdrometers for research, agriculture, or hydrology.

What You'll Build

A solar-powered, IP65-enclosed instrument that logs raindrop count and size bins to a microSD card with DS3231 timestamps. The 0.96-inch OLED displays live histograms, while the MAX9814 mic amplifier captures impact frequencies from drizzle to monsoon bursts. Everything is powered by two 18650 batteries charged via a TP4056 module and 6V solar panel, making it completely independent of mains power for weeks.

What You'll Learn

• Acquire and condition raindrop impact audio with a MAX9814 microphone amplifier for the Arduino Mega’s ADC, filtering electromechanical noise with on-board capacitors.
• Perform real-time FFT analysis to map impact pitch to drop size bins, distinguishing drizzle droplets from heavy rain.
• Log size-distribution data to SD card with DS3231 RTC synchronization, creating a dataset ready for export and analysis.
• Design a solar-charged power supply with lithium battery protection, deep-sleep firmware, and LM2596 buck regulation for long-term outdoor deployment.

Kit Contents

Microphone inside a metal plate distinguishes raindrop impact sounds by pitch to count drop size distribution.

What's in this kit

• Arduino Mega 2560
• MAX9814 Mic Amp
• DS3231 RTC
• MicroSD Module
• 0.96in OLED
• LM2596 Buck Converter
• 100nF Caps x10
• 10kΩ Resistors x5
• PCB Prototype Board x2
• Waterproof Metal Plate
• Waterproof Enclosure
• Solar Panel 6V 1W
• TP4056 Module
• 18650 Cell x2
• 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.