Tag Archives: wireless

19th century radio technology meets the Beaglebone

via Dangerous Prototypes

spark

Ashish Derhgawen built a coherer-based receiver with a simple decoherer mechanism, and connected it to a Beaglebone to decode the received signals:

In my last post, I described how I made a spark-gap transmitter and receiver. For the transmitter, I used a car’s ignition coil to produce high voltage sparks, and for the receiver, I used a coherer to detect the transmissions. A coherer is a simple device – it consists of iron filings between two electrodes. Normally the filings have very high electrical resistance (tens of megaohms), but when the coherer detects electromagnetic waves, its resistance drops to about 10-20 ohms.

More details at Ashish’s blog.

Check out the video after the break.

nRF24L01+ 2.4 GHz wireless connectivity with the tinyK20 board

via Dangerous Prototypes

nrf24l01-transceiver-with-tinyk20

Erich Styger writes:

I’m using the tiny and inexpensive Nordic Semiconductor nRF24L01+ transceiver (see “Tutorial: Nordic Semiconductor nRF24L01+ with the Freescale FRDM-K64F Board“) in many projects: it costs less than $3 and allows me to communicate with a proprietary 2.4GHz protocol in a low power way (see “IoT: FreeRTOS Down to the Micro Amps“). I have that transceiver now running with the tinyK20 board too.

More details at MCU on Eclipse site.

OpenGarage, an Open-source WiFi garage door opener

via Dangerous Prototypes

Ray Wang has published a new project called OpenGarage, an open-source garage door opener based on ESP8266 and the Blynk app:

Today I am very excited to introduce you to OpenGarage — an open-source, universal garage door opener built using the ESP8266 WiFi chip and the Blynk app. I’ve wanted to finish this project for a while, as there have been multiple occasions where I left the house in a hurry and forgot to close my garage door, or locked myself out of the house, or had to let a friend or handyman in while I was away. Having a WiFi-based garage door opener (which I can access remotely using my mobile phone) would be super convenient. Recently as I started learning about ESP8266, I found it to be the perfect platform to help me complete this project.

Project info at Rayshobby.net.

ESP8266 wireless SID project

via Dangerous Prototypes

IMG_3158-600

bl4rk shares his ESP8266 wireless SID in the project log forum:

I’ve been trying to start a SID project for about 5 years now. Back then I wanted to use a 6502 along with a CPLD and other ‘real’ hardware… while I might still do something like that (or even try to use an FPGA for everything except the SID), I think it’s probably good that I waited so long because now this great cheap ESP8266 wireless SoC is around.

Via the forum.

Building a low cost wifi camera

via Dangerous Prototypes

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Johan Kanflo designed a Esparducam board and built a low cost wifi camera with an Arducam Mini and a ESP8266 Wifi module:

Sometime ago I came across the Arducam Mini which is quite a nice camera module from UCTronics. It is a small PCB with a two megapixel OmniVision OV2640 sensor, an interchangeable lens and an FPGA to do the heavy lifting of image processing and JPEG encoding. Priced at around 24 Euros (lens included) you can easily buy a few without hurting your wallet and combined with an ESP8266 you can build quite a low cost wifi camera. Or several. Because designing and building PCBs is both fun and inexpensive I designed a board to go with the ESP8266/Arducam Mini combo, aptly named the Esparducam. And uniquely named too, try googeling for “esparducam“. Heck, even the domain name is available at the time of writing :)

More details at Johan Kanflo’s blog.

Project files are available on Github.