last modified: October 23, 2025
Posted on 2017-04-29— Projects
I describe making a small alpha batch of my low-cost plant-watering sensor: ordering parts, prepping and soldering wires, testing PCB assembly with stencils, and solving sealing with epoxy. If you’re interested in practical prototyping tips and lessons learned, please read the full post for photos and detailed steps.
Posted on 2017-03-03— How and Why
In part three I assemble and test the prototype PCB, set ATtiny13A fuses, and refine user interaction and firmware plans. I cover LED display choices, power measurements and a modular firmware approach. If you’re building a low-cost plant sensor, read the full post for practical steps and diagrams.
Posted on 2017-02-14— How and Why
I take you through part two of my cheap plant-watering sensor project, testing a prototype: power draw, LED impact, oscillator and MCU startup timing, voltage-divider checks, firmware inputs, and PCB preparation. If you want to see the detailed measurements and next steps, I invite you to read the full post.
Posted on 2017-02-08— How and Why
I walked through designing a cheap capacitive plant watering sensor, from goals and measurement options to component selection and early prototypes. I explain why I chose a CR2032‑powered op‑amp oscillator, ATtiny MCU and low‑power timer. If you’re curious, read the full post for details and test results.