ESP8266 – 5$ internet connected switch


EasyIoT @ shows us how to build an Internet connected switch using ESP8266 Wifi module and EasyIoT Cloud service.

In this tutorial we will show how to build WiFi internet connected switch connected to EasyIoT Cloud. We will use ESP8266, solid state relay and Arduino IDE. Switch can be controlled by WEB application, native Android application or button.

This internet switch is “plug and play” – it will automatically set all EasyIoT Cloud settings, so no configuration in EasyIoT Cloud is needed.

ESP8266 – 5$ internet connected switch  – [Link]

Save space on your PCB with TRACOPOWER!


TMLM family of 4-20W AC/DC power supply is the right solution on most important requirements – constraint space, high efficiency and cost saving.

Every square inch of your PCB costs money. It is a fact, and if you can reduce your PCB´s area, you actually save money. Moreover if you use a high efficiency power supply you save energy.The TMLM Series switching power supplies, offer highest power density in a fully encapsulated module which can be soldered directly on to PCBs. This feature makes these modules an ideal solution for all space critical applications in commercial and industrial electronic equipment. International safety approvals qualify the product for worldwide markets. SMD-technology and high efficiency guarantees a high reliability of these Power Supplies.

Save space on your PCB with TRACOPOWER! – [Link]

Build a Simple Toaster Oven Temperature Profile Controller


Maurizio @ has tipped us about his latest project. In this article he discuss how to build a simple toaster oven temperature profile controller using StickOS and CPUStick. This is the first part of the article.

Using a highly-integrated microcontroller running “StickOS BASIC”, it is possible to quickly build a toaster oven temperature profile controller for performing surface mount (SMT) printed circuit board reflow soldering at home. It is also possible to program a large variety of other general-purpose embedded system projects with minimal software effort, using only a terminal emulator and high-level BASIC algorithmic statements to manipulate the microcontroller (MCU) pins and peripherals.

Build a Simple Toaster Oven Temperature Profile Controller – [Part 1] [Part 2]

ESP8266 DIY Wifi Smoke Alarm Notifier

22114918954_23cf9717c9_k1-750x429 has build a Wifi connected smoke alarm using ESP8266 module:

This tutorial will teach you how to build a Wifi Smoke Alarm Notifier for about $10 dollars. You won’t have to code anything, and you won’t have to solder or buy expensive electronics equipment. Any services you are asked to use will be 100% free. Its that easy. Lets get started!


One of the reasons why IoT devices can be built so easily now is because of the ESP8266 development board. IoT enthusiasts have been excited about the ESP8266 because its a full system on a chip (SoC) that has onboard wifi connectivity that can cost as low as 3 dollars.

ESP8266 DIY Wifi Smoke Alarm Notifier – [Link]

Single Regulator contains buck and boost controllers


Linear Technology Corporation introduces the LTC7812, a dual output (boost + buck), low quiescent current synchronous DC/DC controller. When cascaded, its independent step-up (boost) and step-down (buck) controllers regulate the output voltage from an input voltage that can be above, below or equal to the output voltage, maintaining output regulation during cold crank and load dump conditions. Unlike conventional single inductor buck-boost regulators, the LTC7812’s cascaded boost + buck solution provides fast transient response with continuous, non-pulsating, input and output currents, substantially reducing ripple voltage and electromagnetic interference (EMI), making it ideal for automotive, industrial and high power battery operated systems.

Single Regulator contains buck and boost controllers – [Link]

Bluetooth enabled Door locker using Arduino


Frank Donald @ has build a bluetooth controlled door locker using Arduino. Source code included:

DIY Arduino based lockers can be found plenty in the internet where keypad was used to feed lock input. But this Bluetooth enabled Door locker uses Bluetooth as a medium to connect with the locker and your smart phone to feed input credentials. This locker allows you to lock/unlock your locker without physical touch when you are within the range of Bluetooth communication.

Bluetooth enabled Door locker using Arduino – [Link]

Component Tester FISH 8840 Review


Alan Parekh @ has a review of a cheap component tested he found on ebay. This device can test bipolar transistors, MOSFET, diodes, thyristors, resistors and capacitors. He writes:

This is an inexpensive component tester called the FISH 8840 which you can find from many online eBay retailers for around $30. The interface is very simple, attach a device to be tested and press the test button. It turns off after about 20 seconds, pressing the off button puts it into sleep mode immediately. There is a ZIF socket that allows you to insert leaded devices and pads that allow you to press SMD devices directly onto the tester.

Component Tester FISH 8840 Review – [Link]


ATtiny 85 EMF detector


arduinomaster @ has build an EMF detector based on ATtiny85 mcu able to detect signals from 0-999Hz. He writes:

An EMF meter can measure AC electromagnetic fields, which are usually emitted from manmade sources such as electrical wiring, while gaussmeters or magnetometers measure DC fields, which occur naturally in Earth’s geomagnetic field and are emitted from other sources where direct current is present.

ATtiny 85 EMF detector – [Link]


Raspberry PI and DHT22 Temperature and Humidity logger


“jjpfin” @ build a Raspberry Pi based temperature and humidity datalogger using DHT22 sensor. Data is stored on mySQL server and can be viewed on browser.

This is an Raspberry Pi based temperature and humidity logger that uses 2 (works also with 1) Adafruit DHT22 sensors for measurements. You might have seen similar kind of instructions before, but this one has a twist. It doesn’t just read temperature and humidity from sensors, but it stores data to MySql database and provides means to read that temperature data with any web enabled device (computer, phone, tablet) web browser.

Raspberry PI and DHT22 Temperature and Humidity logger – [Link]

OpenCVMeter – Rediscover Your Capacitors


OpenCVMeter is an open source tool to measure capacitance and leakage current as a function of a capacitor’s working voltage.

When designing circuits, many hobbyists take capacitors for granted – but each type (ceramic multi-layer, aluminum electrolytic, tantalum, mica…) has its own unique properties. Nowadays, ceramic capacitors are the most commonly used capacitors in the industry, but many can lose up to 80% of their rated capacitance near their voltage ratings.

Enter the OpenCVMeter! This meter aims to provide a Capacitance versus Voltage characterization accurate within 1% of the capacitors for your next project (or already have and are starting to wonder about right now…)

OpenCVMeter – Rediscover Your Capacitors – [Link]