Learn to Solder - DIY Ultrasonic Ranging Electronic Kit

A DIY soldering kit that builds into a functional ultrasonic distance meter. Using an HC-SR04 ultrasonic sensor, STC89C52 microcontroller, and 3-digit 7-segment display, this kit measures distances from 5cm to 4m with a built-in buzzer alarm when objects get too close.

The microcontroller comes pre-programmed, so once assembled the device is ready to use. Set your distance threshold using the onboard buttons – the buzzer sounds when objects are closer than your set value. Settings are retained after power-off.

Key Features

• 5cm to 4m Range – Accurate ultrasonic distance measurement displayed on 7-segment LED
• Adjustable Alarm – Set a distance threshold; buzzer alerts when objects are closer
• Pre-Programmed MCU – STC89C52 microcontroller comes ready to run
• Button Controls – Adjust settings with +, -, and Set buttons
• Memory Retention – Alarm settings saved after power-off
• USB or Battery Power – Includes both USB cable and battery holder

Ideal For

• Learning through-hole soldering with a functional result
• Understanding microcontroller-based sensor projects
• DIY parking sensors and proximity alarms
• STEM education and electronics workshops

Specifications

• Measurement Range – 5cm to 4m
• Display – 0.56" 3-digit 7-segment LED
• Microcontroller – STC89C52 (pre-programmed)
• Sensor – HC-SR04 ultrasonic module
• Input Voltage – DC 4.5–5.5V
• PCB Size – 60 × 70mm
• Assembled Size – ~60 × 90 × 30mm (with sensor)
• Weight – 80g

Kit Contents

• 1× PCB
• 1× HC-SR04 Ultrasonic Sensor Module
• 1× 0.56" 3-digit 7-segment Display
• 1× STC89C52 Microcontroller (pre-programmed)
• 1× 40-pin IC Socket
• 1× 12MHz Crystal Oscillator
• 1× 5V Active Buzzer
• 1× 5mm Red LED
• 3× Tactile Buttons (6×6×12mm)
• 1× Power Switch with Cap
• 1× DC005 Power Jack
• 1× USB to DC Power Cable
• 1× 3×AA Battery Holder
• 4× 9012 Transistors
• 9× 1KΩ Resistors
• 7× 4.7KΩ Resistors
• 3× 22pF Ceramic Capacitors
• 1× 10µF Electrolytic Capacitor