Homemade 6 GHz FMCW radar

Henrik Forstén has a nice build log on his newest version of this homemade 6 GHz FMCW radar:

Frequency Modulated Continuous Wave (FMCW) radar works by transmitting a chirp which frequency changes linearly with time. This chirp is then radiated with the antenna, reflected from the target and is received by the receiving antenna. On the reception side the received signal that was delayed and undelayed copy of the transmitted chirp are mixed (multiplied) together.

Homemade 6 GHz FMCW radar – [Link]

4chord MIDI Plays All the Hits

4chord MIDI – the USB MIDI keyboard to play every major hit pop song with four little buttons. by Sven Gregori:

4chord MIDI – the USB MIDI keyboard dedicated to play all the four chord songs, from Adele via Green Day and Red Hot Chilli Peppers to U2 and Weezer. Thanks to MIDI, you can be any instrument – and all of them at once. Yay!

4chord MIDI Plays All the Hits – [Link]

1Bitsy ARM Cortex-M4F Dev Board

Open-Source Miniature Breadboard Friendly ARM Cortex-M4F Dev Board with 1MB Flash, 196kB RAM, 168MHz, floating point and more.

1Bitsy is a debuggable open source STM32F415 development board. Designed for beginners as well as advanced users that want more control over their embedded software by exposing the JTAG/SWD debug interface that is compatible with the Black Magic Probe JTAG/SWD debugger with built in GDB server.

1Bitsy ARM Cortex-M4F Dev Board – [Link]

GnuBee Personal Cloud 2

The GnuBee is live on crowdsupply.com.

The GnuBee Personal Cloud 2 (GB-PC2) is a network-attached storage (NAS) device specifically engineered to run free, libre, open source software (FLOSS). The GB-PC2 has all the functionality of any commercial, proprietary NAS, but at a much lower cost and with the transparency, reliability, and accessibility advantages that come with using FLOSS.

GnuBee Personal Cloud 2 – [Link]

Arduino Weather Station With E-Ink Display

Arduino Uno home weather station with e-ink display The hardware used for this project is:

  • Waveshare 4.3 e-ink display
  • Arduino Uno
  • Adafruit BME280 combined temperature, humidy and atmospheric pressure
  • DS3231 based hardware clock

Arduino Weather Station With E-Ink Display – [Link]

Researchers Developed Highly Durable Washable And Stretchable Solar Cells

Scientists of Japanese research institute RIKEN and the University of Tokyo have successfully developed a product that allows solar cells to continue to provide solar power after being washed, stretched and compressed. Takao Someya of Riken Center for Emergent Matter Science, a designated national R&D Institute in Japan, led the research team.

Washable and stretchable solar cell
Washable and stretchable solar cell

The research results were published in the journal Nature Energy and illustrated a photovoltaic material that could be used to make washable outer garments and wearable devices. The researchers say that the innovated solar cells will be a power source to low-power devices and can also be worn concurrently. This innovation might solve one of the biggest challenges of the Internet of Things (IoT), the requirement of a reliable power source to keep all devices connected.

The newly invented solar cells could power wearable devices that include health monitors and sensors for analyzing the heartbeat and body temperature. This could make prevention and early detection of potential medical problems possible. Though the concept of wearable solar cells is not unique, the previous wearable solar cell solutions suffered from the lack of one vital property i.e. long-term stability in air and water, including resistance to deformation.

The recent stretchable solar cell innovation has successfully achieved all of the most important features and is creating the way for the top-notch quality of modern wearable technology. The material on which their new device is based on is called PNTZ4T – a highly efficient polymer solar cell capable of small photon energy loss. The scientists deposited the device onto a parylene film which was then placed onto an acrylic-based elastomer. The construction method has proved to be particularly very durable.

The device produced 7.86 milliwatts per square meter based on a sunlight simulation of 100 milliwatts per square meter before considering resistance and durability. It showed the least decrease in efficiency when soaked in the water and when stretched. The efficiency decreased by only 5.4 percent and 20 percent respectively. Kenjiro Fukuda of RIKEN Center for Emergent Matter Science said,

We were very gratified to find that our device has great environmental stability while simultaneously having a good efficiency and mechanical robustness. We very much hope that these washable, lightweight and stretchable organic photovoltaic will open a new avenue for use as a long-term power source system for wearable sensors and other devices.

ME Labs Advanced D-Stick (PIC18F47K40)

melabs.com released a new development board based on PIC18F47K40 PIC microcontroller. The board includes everything you need to start with your project. Documentation here: http://melabs.com/dstick/

The ME Labs Advanced D-Stick provides all the functionality of Microchip’s 40-pin PIC18F47K40 in a hardware module that includes a USB on-board programmer and virtual COM port. The D-Stick is a compact, simple and easy to use alternative to connecting a serial port, programmer, power supply, etc. to a solderless breadboard for project development. After development, simply replace the D-Stick with the pinout-compatible, production-ready PIC18F47K40.

ME Labs Advanced D-Stick (PIC18F47K40) – [Link]

STM32 Arduino Tutorial – How to use the STM32F103C8T6 board with the Arduino IDE

In this Arduino Tutorial, we are going to take a first look at the STM32 Arduino Compatible Board. This board is powerful and inexpensive. Let’s see what it has to offer!

STM32 Arduino Tutorial – How to use the STM32F103C8T6 board with the Arduino IDE – [Link]

15V 1A Dual Output Flyback DC-DC Converter

+/-15V 1A Dual output DC-DC converter is a tiny board built using Transformer from Renco and LM2587-ADJ IC from Texas instrument.  Input supply 18-36V DC.  The LM2587 regulators is monolithic integrated circuit specifically designed for fly back, step-up (boost), and forward converter applications. The power switch is a 5.0A NPN device that can stand-off 65V. Protecting the power switch are current and thermal limiting circuits, and an under voltage lockout circuit. This IC contains a 100 kHz fixed frequency internal oscillator that permits the use of small magnetics. Other features include soft start mode to reduce in-rush current during start up, current mode control for improved rejection of input voltage and output load transients and cycle-by-cycle current limiting. An output voltage tolerance of ±4%, within specified input voltages and output load conditions, is ensured for the power supply system.


  • Supply Input 18-36V DC
  • Output +/-15V DC, 1Amp
  • On board trimmer potentiometer for Fine voltage adjust
  • Operation Frequency 100 KHz

15V 1A Dual Output Flyback DC-DC Converter – [Link]

GAME BYTE – Retro gaming system

Game Byte the open source gaming system for creating, sharing, and playing games is live on kickstarter. Over 100 free games. Make your own games.

Game Byte is an open source gaming system for creating, sharing, and playing games. It’s SMALL! About the size of a credit card and fits in your pocket so you can take it with you wherever you go. You can play one of the over 100 free games available or learn how to create your own. The built in microSD card slot allows you to store your games on an SD card without plugging into a computer.