You got it—here’s a no-nonsense breakdown of the $30 prototype TDS tester setup, how to hook it up, and what to post to hand this idea off to a builder.
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$30 iPhone-Connected Water Quality Tester (TDS) – DIY Kit List
Parts List (Prices Approximate - New)
1.TDS Sensor Module (Gravity Analog TDS by DFRobot) – $11.80
2.ESP32 Development Board with Bluetooth – $12.00
3.Wiring/Connectors – $3.00
4.Basic USB battery or connector – $3.00
Optional Add-ons:
• Enclosure (3D-printed or project box) – $5.00
• pH Sensor (if desired) – $20.00
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Verbal Schematic / Build Instructions
1.Power the ESP32 using a USB battery pack or USB wall adapter.
2.Connect the TDS sensor’s analog output to one of the ESP32’s analog input pins (e.g., GPIO34).
3.Connect sensor’s GND and VCC to the ESP32’s GND and 3.3V.
4.Program the ESP32 (using Arduino IDE or similar) to read the analog voltage, convert it to TDS (ppm), and transmit the value over Bluetooth Low Energy (BLE).
5.On the iPhone, use a simple Bluetooth terminal app, Apple Shortcuts, or even Web BLE in Safari to receive the value and display it.
6.Optionally, build a minimalist UI with Swift or Blynk if you want it branded.
What you end up with: a TDS meter that wirelessly sends readings to your iPhone, using cheap, existing components. No need to reinvent a thing—just plug it together and code light.
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Hashtags:
#OpenSourceWater #TDSmeter #CleanWaterTech #ESP32 #iPhoneHack
Mentions:
@arduino
@adafruit
@DFRobotcn
@ESP32net
@OpenSourceOrg
@iFixit
@hackaday
@techreview
@Makerspace
@Instructables
@AdafruitInd
@Blynk_Official
@Waterkeeper
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Anyone out there want to build it? Take the baton and run with it. Let’s keep the water clean, and the tech simple.