PlantLab: A Complete Open-Source IoT Plant Care Kit for Beginners (Part 1: Hardware & PCB)

PlantLab open-source IoT plant care kit feature image with the final controller build

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

Building a Battery Meter for Field Radio Operation

Feature image with the title "Building a Battery Meter for Field Radio Operation" over a realistic workbench scene showing a yellow battery meter and a 4S LiFePO4 battery pack.

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

AC vs. DC: What Is the Difference and How Can You Tell?

Simple comparison of a steady DC line and an alternating AC sine wave.

Welcome back to our Electronics Basics series. In the previous lesson, we explored voltage, current, and resistance. This lesson focuses on the two main forms of electric current you encounter every day: direct current (DC) and alternating current (AC). Their essential difference is direction. Conventional current in a DC circuit flows in one direction, while … Read more

Voltage, Current, and Resistance Explained with a Water-Pipe Analogy

Simple circuit diagram identifying voltage, current, and resistance.

Welcome back to our Electronics Basics series. In the first two lessons, we learned about electrons, electric charge, static charge, and electric current. Now we will explore three fundamental electrical quantities—voltage, current, and resistance—and see how they work together. We will use a water-pipe analogy to make the ideas easier to visualize. Like any analogy, … Read more

Build a J-Pole Antenna for Your LoRa Meshtastic Base Station

Feature image showing a rooftop LoRa Meshtastic base station with a homemade PVC J-Pole antenna and solar panel

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

Electric Charge, Static Charge & Current

an illustration showing pcb trace, with blue circles representing current and red circles representing static charge

Welcome back to our Electronics Basics series! In the last lesson, we got to know electrons—the tiny, negatively charged particles that make all electronic devices work. Today, based on that foundation, we’ll explore three core concepts: electric charge, static charge, and current. By the end of this article, you’ll understand the key concepts of these … Read more

What Is an Electron? From Atomic Structure to Electron Flow

Illustration of glowing blue electrons moving through a circuit board with the title "Electronics Basics 01: What Is an Electron?"

Welcome to the first entry in our Electronics Basics series! To understand how your phone, computer, or even a simple flashlight works, you must first get to know the “star” of the show: the electron. Without the movement of these tiny particles, electronic technology as we know it simply would not exist. 1. Atomic Structure: … Read more

Lora Meshtastic Nodes Built from Scratch Part 2

a solar meshtastic CLIENT_BASE Station deployed on balcony rail

In Part 1, we built Meshtastic nodes from custom made boards. Now in Part 2, we’ll turn one node into a permanent, always-on CLIENT_BASE station powered by solar, mounted outdoors on my balcony. This base station will act as the backbone of my local Meshtastic network, while the second node will be a portable tracker/handheld … Read more

Lora Meshtastic Nodes Built from Scratch Part 1

meshtastic node esp32 custom board feature image

This article details how to build a fully custom Meshtastic LoRa mesh node from zero. It covers open‑source PCB design, component assembly, firmware compilation, 3D printed enclosure, and final configuration for off‑grid, long‑range communication. Overview Meshtastic is an open-source communication protocol that transforms affordable LoRa (Long Range) radio modules, typically powered by “ESP32” or “nRF52” … Read more

A 260W Multi-Port Desktop Quick-Charge Unit

desktop charger 260w two type-c ports

Nowadays, we use more and more electronic devices in daily life and work—like smartphones, tablets, laptops and smart wearables. Our need for quick charging is growing fast. Some people may always feel they don’t have enough charging ports on the desktop. To fix this issue, here comes a project, which is an open-source DIY desktop … Read more