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DIY Capacitance Meter


We are building another opensource project which is very enjoyable to build and use. In our electronics works, we frequently need to know the actual value of a capacitor. As you know, small sized SMD capacitors have no markings showing their values. Or there are lots of fake electrolytic capacitors which are rated much lower than their stated values. Sometimes the capacitors have large tolerances and we want to choose the best fit for our circuit. What we need is an accurate capacitance meter.

This is a capacitance meter which can measure capacitors rated from picofarads to millifarads. The principle of operation is simple. Just apply voltage to the capacitor and measure the elapsed time to charge it. The circuit is based on Atmega328P and it is Arduino IDE compatible. It includes the voltage regulators which output 5V and 3.3V from 9V input. A Nokia 5110 LCD is used to display the measured information. Thanks to the 4mm banana jacks, various kinds of probes can be used such as SMD probe, crocodile probe etc.

Alarm Clock Powered by PIC24


How many times do you need to set your alarm clock before you actually climb out of bed in the morning?

We all have a tendency to check an alarm clocks setting at bed time to make sure it is set right. This clock is almost similar to the one the author previously made, instead of using MSP430 but PIC24. RTCC pheripheral was used for timekeeping while LifePO4 battery as the source of power supply that is charged using USB charger. He also used photo transistor to dim the display in the dark.

As always the author is kind enough to include the source code for us to understand how the project runs. You can also watch the video which walks us through the process. For the display, he used a 7 segment display included with MOSFET placed under it.  This bedside alarm clock has what you’d expect from an alarm clock.

Very Simple but Complete FM Radio


FM radio can be complicated to build, but not this one. This FM radio is about the easiest you can possibly make with only a few components.

This is a very interesting and simple project in the series of communication used to transmit noise free FM signal in the wide range using only one transistor. Because this is a super generative design, component layout can be very important. The power source for this radio is from a 9V battery. The assembling turns out well and you can now start to enjoy your very own radio.

Though the science of radio is well understood, there’s a magical, emotional quality about it that we don’t often stop to appreciate. You will not forget the first time you pick up a transmission broadcast from a device you soldered together, yourself, from a few bits of copper, carbon, plastic, and wire.

Raspberry Pi Utilized for Mini Weather Station


It is possible to control the Weather Station with an embedded board such as the Raspberry Pi. You can put the Raspberry Pi in the case, despite it is a bit tricky to get everything in the case.

The goal to this tutorial is to create a simple weather station to check temperature and humidity: we will look at how to get the data from a sensor, send it and then retrieve it to display it on a web page. That data is then acted on or observed for later; in this case temperature and humidity. The sensors used were from Adafruit as they are fast and very refutable. The instructions should be fairly accurate for other Linux distributions as well because this project has been tested with a fresh install of Raspian.

As the author said, this project has been going on for a while and lately, getting cheaper and easier to do. Now, after the completion of this tutorial, you can now measure temperature, humidity, pressure and Lux.

SEPTEMBER GIVEAWAY: Raspberry Pi 2 – Single Board Computer

UPDATE 07/10/2015: The winner is randomly selected.

Красимир Стефанов



We are offering Raspberry Pi 2 Single Board Computer to Electro-Labs readers.
Some basic rules apply:

  • The giveaway will last from 01 Sep 2015 to 30 Sep 2015
  • One random winner will be selected and the gift will be shipped free of charge worldwide.
  • To participate, (1) like Electro-Labs FB Page by using the like-page button, (2) share this post by using the share-button button in the container below.
  • (3) Leave your comment.
  • One random winner will be selected from readers who completed these three steps and the gift will be shipped free of charge worldwide.

Control Anything at Your Home with Netflix Switch


Netflix has become the number one way to get movies without physically renting them. You can sign up for a Netflix account and choose a subscription.

The new do-it-yourself Netflix button prepares you for binge watching your favorite TV series on long and lazy nights without even touching your phone. The button is set to dim the lights, switch your phone to do not disturb, order takeout food, and, of course, turn your TV to Netflix. It’s essentially with the simple purpose in mind that you could have everything needed for a movie night at the press of a button and the use of an app.

For those who want to give the Netflix switch a try, they will need a microcontroller, a polymer lithium ion battery with a Micro USB jack, a transistor, a resistor kit, an infrared LED, and an actual button, along with a smartphone. The device will connect to your TV, home wireless network, your phone and the in-home smart lighting system.

Interactive Name Tag with LCD Display


This project was built as an interactive name badge for conferences and social events that significantly improves the quality of people-to-people connectivity. It also brings social technology into the event arena where both host and attendees derive numerous benefits compared to the paper badges of the past.

It is consists of an I2C LCD screen, an ATtiny85 microcontroller and a microphone and powered by 500 mAh LiPo battery. Components were connected through terminals making it easily changeable and the system scalable. The designer used Attiny85 microcontroller because it is low power consumption, size and also its price. Every part was fitted behind the screen as well as the battery and the on/ off button were placed on the side.

This is worn like regular paper badges and what so good about creating this, is all the components used were cheap and can be easily bought.

Indoor Ambient Quality Monitor Known as SXAM


This project helps people make better air quality decisions by helping them with cost effective and reliable instrumentation and information. Sensor-based instruments and air quality monitoring systems are used widely in outdoor ambient applications as well as indoor air quality.

With that purpose, the designer of this project build an indoor ambient quality monitor that is able to measure temperature, humidity, noise and brightness and indicate the ambient quality using LEDs. The measurements are recorded on to the platform, as well as displayed locally to the user through 4 bi-color led indicators.

The simple PCB was simple and used as the bridge for the Arduino and sensor board as well as the main board and sensor can be design as single board. A step down switching regulator was recommended to be use because temperature and humidity sensor heats up.