Tag Archives: radio hacks

Developed on Hackaday – HaDge is back to the drawing board

via Hackaday » hardware

A couple of days back, we wrote about the HACK – a prototyping platform designed by [Michele Perla] based on the Atmel SAM R21 MCU. It’s one of the new breed of devices consisting of an ARM Cortex-M0 MCU + IEEE 802.15.4 Wireless radio bundled together. This was exciting since we could pack a lot of punch in the HaDge hardware. We planned to use the same design later to power the HaDge. Building HACK would have allowed us to get it in the hands of the software team, while the hardware folks worked on the real HaDge layout.

The HACK design was ready for review and we asked around to verify the antenna layout, which was the part we were not too sure about.  We asked Atmel for help with verifying the layout. That’s when we had the facepalm moment. They asked us – “What about FCC certification?” Since we plan to build the badges in quantities of a few hundred at the very least, it’s obvious we cannot escape from FCC certification. A design based around the R21 is ruled out – the cost of obtaining approval is pretty high. This means we need to punt the R21 and instead use an off-the-shelf radio module which is already FCC certified. Sigh.

Now the good news. This is a setback in terms of time, and effort put in by [Michele]. But beyond that, we’re good to go back to the drawing board and start afresh. First off, we decided to revert back to the Atmel D21 as the main controller. It’s a fairly decent MCU, and there’s a fairly robust tool chain available that a lot of people are familiar with. For the Radio, we are looking at some of these available options :

The last one from Microchip looks quite promising. But we’re open for better and cheaper suggestions, so please chime in with your comments.

Filed under: Hackaday Columns, hardware, radio hacks

Spectrum Painting on 2.4 GHz

via Hackaday » hardware

Give a software-defined radio (SDR) platform to a few thousand geeks, and it’s pretty predictable what will happen: hackers gotta hack. We’re only surprised that it’s happening so soon. Spectrum Painter is one of the first cool hacks to come out of the rad1o badge given out at the CCCamp 2015. It makes it dead-simple to send images in Hellschreiber mode on a few different SDR hardware platforms.

What we especially like about the project is its simplicity. Don’t get us wrong, we’re tremendous fans of GNURadio and the GNURadio Companion software radio hacking environment. But if you just want to do something simple, like send a picture of a smiley-face, the all-capable GNURadio suite is overkill.

HackRF, the rad10 badge, and bladeRF all have software that enables you to directly load up and play out a file over the radio interface; it’s like a WAV file, only at radio frequency. This makes a hack like Spectrum Painter pretty straightforward. Simply convert the image file into the corresponding radio waveform data, and send it along. No GUI, no dragging, no dropping.

img2iqstream -s 1000000 -l 0.004 -o smiley.iqhackrf --format hackrf examples/smiley.png
hackrf_transfer -t smiley.iqhackrf -f 2450000000 -b 1750000 -s 1000000 -x 20 -a 1

Bam! Kudos [polygon]!

If all of this SDR action has your interest piqued, there’s a lot you can do even just receiving with an el cheapo RTL-SDR USB stick. It’s the gateway drug into SDR, so if you’re not addicted yet and you’ve got a free weekend, give it a shot.

Filed under: hardware, radio hacks