Electronics DIY kits are easy to find from either Arduino kits, or robotics kits, to oscilloscope kits among others. But I can’t remember ever seeing digital scale kits, maybe because I did not look for it, but that’s exactly what I found on ICstation for $27.99 with a scale that can measure weights up to 10 kilograms with a reported one gram accuracy. The DIY scale can also be pruchased on eBay for $29.99.
- MCU – STC MCU Limited STC89C52 8-bit (80C51 compatible) MCU in 40-pin DIP package
- RTC – DS1302 8-pin DIP chip + CR1220 socket and battery
- EEPROM – AT24C02 serial EEPROM (DIP chip)
- Display – LCD1602 16×2 digit display
- Keypad – 4×4 matrix keypad
- Sensors – DS18B20 one-wire temperature sensor, “C3 high precision” 10kg strain pressure sensor
- Boards – HX711 load cell amplifier module, printed circuit board for the MCU, RTC, EEPROM, etc…
- Misc – Buzzer, transistors, various passive components
- Enclosure and accessories
- Power Supply – 5V DC
- Dimensions – 15.2cm x 14.1cm x 6.5cm (assembled)
- Weight – 500 grams
Follow the assembly guide to build the scale yourself, and you should be good to good to use your own scale/clock/alarm/thermometer toy.The scale could also be the starting point to make your own design either programming the STC89C52 micro-controller with your own program (AFAIK source code is not available so you’d have to start from scratch), or possibly “IoTize” the scale by replacing the MCU by a Bluetooth or WiFi (ESP8266) module.
Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.