Category Archives: how-to

ESP8266 + DS18B20 Temperature sensor sends data to Thingspeak.com

Mohamed Afzal has written an article detailing how to send data to Thingspeak.com with ESP8266 + DS18B20 temperature sensor: The stock Firmware in the ESP8266 supports AT commands and for communicating with this need an micro-controller like Arduino. But i want to make a simple solution for that without using external micro-controller. NodeMCU firmware was the best thing […]

Great results milling PCBs from Eagle with the Nomad

Liyanage over at Carbide 3D Community site writes: Milling PCBs was one of my main reasons for getting a Nomad. I finally found some time to learn how to use Eagle and the related tools and mill my first boards. While diving into the intricacies of these tools, I came across a forum discussing non […]

Soldering Iron PID temperature controller

Mike has posted a detailed tutorial on how to modify an ordinary plugin soldering iron to work with a digital temperature controller: A thermocouple was mounted internally inside the soldering iron so it is out of the way. The idea was to find the “sweet spot” at the back of the heating unit inside the soldering iron […]

Use ESP8266 module as a wireless switcher

Razvan Dubau over at Extragsm posted a how-to on using an ESP8266 module as a wireless switcher: A custom firmware to transform the ESP8266 wifi module into a wifi http based switcher GPIO02 is used as an output pin. You can connect a led or a relay and controll it by a button added to GPIO00. Also the […]

Laser etching SMT stencils tutorial

Felix Rusu of LowPowerLab has posted a detailed tutorial on how to laser etch SMT stencils: In this blog post I want to show you my new method that I’ve been using since I’ve purchased a laser cutter from china. It’s using the laser to etch stencils out of transparency plastic (mylar). Chances are that you already have […]

Low power magnetic hold and release mechanism

This video by Shane Ormonde discusses the low power magnetic hold and release mechanism: With the inductor and magnet combined, ferrous metal objects can be held without any power indefinitely. To release the metal object the magnetic field holding it up needs to be temporarily cancelled out. This happens by pulsing current through the inductor which generates […]

Systematic PCB verification approach

From the comments on our previous PCB Checklist post, George Hadley shared this helpful checklist for submitting a PCB to a fab house: Systematic PCB Verification Approach (PDF!): 1. Parts completion check: 1. All major components included? Microcontroller/FPGA/SoC/Microprocessor/CPLD? Power supply/regulation? Sensors? User interface elements? (LCDs, buttons, switches, etc.) Actuator drivers and control? (Motor control? LED constant current drivers? […]

jQuery Plugin that formats JSON strings

  Matthew Heironimus writes: This jQuery plugin is based on a nice little JavaScript routine written by Vladimir Bodurov that can be viewed at www.bodurov.com/JsonFormatter. To use this plugin include jsonFormatter.min.css and jsonFormatter.min.js in your html file. See the jsonFormatterExample.html file for an example on how to do this. If you wish to use the darkTheme, […]

PCB Checklist – What to check before you submit

Baldengineer’s checklist for submitting a PCB to a fab house: Recently I’ve been expanding my retro game collection to include game cartridges imported from Japan. The problem is that I don’t have Japanese game systems (yet). So I’m creating an open source adapter to convert Famicom carts to the NES. Before I submit the PCB to […]

ESP8266 WiFi module quick start guide

follower from rancidpacon writes, I recently wrote a 15-page getting started guide for the $5 ESP8266 WiFi modules for Kiwicon 8, a local New Zealand hacker con. It’s available as both HTML and a PDF. It provides details on: how to make the hardware connections using an FTDI Board or Arduino (with suitable disclaimer); how […]

Build a 16 million color WiFi-controlled LED lamp

Tom Van den Bon and Sebastian Schocke of Binary Space, a makerspace in the Vaal Triangle, have put together this build challenge for their members. For December at Binary Space we wanted to do something a cheerful and colourful. We got together to design and build a low power LED table or ceiling lamp that […]

Better SPI Bus design in 3 steps

Paul over at Dorkbotpdx has written an article on 3 steps to good SPI Bus design: A much better SPI bus design can prevent conflicts. 3 simple improvements are needed: Use pullup resistors on all chip select signals. Verify tri-state behavior on MISO: use a tri-state buffer chip if necessary. Protect bus access with SPI.beginTransaction(settings) and SPI.endTransaction().

How-to install open source USBasp and USBtiny drivers on Windows

Ray writes with this technique for installing open source drivers on Windows. I came across a surprisingly simple approach to installing USBasp and USBtiny drivers for all versions of Windows — XP, 7, 8, 8.1, whether 32-bit or 64-bit, all inclusive! As you may know, installing open-source drivers such as USBasp and USBtiny have been […]

Soldering headers without drilling holes

rampadc shared detailed instructions of how to solder headers without drilling holes: During a moment of weakness and extreme laziness, the idea of soldering a through-hole header as normal SMD components popped up. This method is probably quite old and may had been used by a lot people but since all homemade PCB guides I […]

Getting character LCDs to work at 3 volts

Peter Jakab has written a new article on how to adapt character LCD modules for 3 volt operation. Generic character LCD modules contain an industry standard HD44780 compatible controller, which can operate down at 3 volts. But the modules are usually specified to work only at 5 volts, unless you choose a specific one designed […]