1. Introduction PlantLab is a beginner-friendly, open-source IoT plant care system built around a simple principle: use easily accessible, off-the-shelf modules—most of which you can buy on Amazon or AliExpress. No custom, hard-to-source parts, just affordable, ready-made modules and regular components. The purpose of the PCB is to link these modules together with connectors and … Read more
When doing the field radio operation, the battery is always one of the things I care about most. For a small QRP station, the power problem is usually not very difficult. The current is low, and a modest battery could last for a long time. But I do not always run QRP. Sometimes I want … Read more
Disclosure: This is an independent introduction to SmartChamber-3D by maker ‘physton’. I am not the author of this project. The goal is to help makers decide whether it is worth studying, adapting, or building. Overview SmartChamber-3D is a chamber temperature control system for enclosed Bambu Lab P2S or P1S 3D printers. According to the OSHWHub … Read more
A More Efficient Antenna Is Needed for the Base Station To improve my Meshtastic base station’s ability to rebroadcast weak LoRa packets, I decided to replace the commercial “rubber ducky” coiled antenna with a homemade J-Pole antenna. While rubber ducky antennas are convenient for handheld devices, they are much less effective for a CLIENT_BASE node. … Read more
Disclosure: This is a review of the open-source project from maker TheLight, named “A Music Visualizer Clock.” It’s a small DIY desktop gadget that combines a digital clock, music visualizer, and environment sensor. The ultra-low power feature is the highlight of the project. We’re now sharing this handy maker project with electronics hobbyists around the … Read more
Disclosure: This article reviews an open-source hardware project by lvyiwuhen, “A Filament Dryer with PID Control,” which is a practical FDM 3D printing accessory designed for reliable filament drying with precise temperature control. We aim to share this functional hardware project, which solves a real 3D printing pain point, with the global hobby electronics and … Read more
Electronics Tools Ohm’s Law Calculator Solve voltage, current, resistance, and power for basic DC circuits. Pick the unknown value, enter the other two values, and the calculator handles the unit conversion. Ohm’s law diagram Voltage, current, and resistance arranged around the Ohm’s law relationship. V I R V = I x R What this tool … Read more
Electronics Tools LED Resistor Calculator Choose a current limiting resistor for a single LED. Enter the supply voltage, forward voltage, and target LED current to estimate resistance, heat, and a practical standard resistor value. LED with current limiting resistor A simple DC circuit showing a supply, resistor, LED, and ground return. +Vs R LED GND … Read more
Electronics Tools Voltage Divider Calculator Calculate a two-resistor voltage divider. Solve for output voltage, input voltage, R1, or R2, then check divider current and resistor power before using the values in a real circuit. Voltage divider schematic Two resistors in series from input voltage to ground with output taken from the middle node. Vin R1 … Read more
Electronics Tools Resistor Color Code Calculator Decode 4-band and 5-band resistor color codes into resistance and tolerance. Use it when reading through-hole resistors in Arduino, ESP32, sensor, and breadboard circuits. Resistor with color bands A through-hole resistor with live color bands and metal leads. color bands to value significant digits x multiplier, then tolerance What … Read more