Door alarm using Micro:bit

This Micro:bit is a small microcontroller designed to teach kids about programming. As well as the CPU, it has a 5x5 LED array for graphics, two buttons, an accelerometer, compass, thermometer, light meter, Bluetooth and a radio interface so that multiple of the boards can talk to each other. There's also 23 pins for different types of IO you can do, including attaching things like sensors, LEDs and speakers for audio. All this for AUD$25 including a battery pack so you can run it disconnected from the computer. Amazing!

Louis and I have been having loads of fun with it. It's really easy to get code onto it. You write programs in the Scratch-influenced visual editor environment and hit the [Download] button to download the program as a .hex file. You plug the Micro:bit in with USB and it shows up as a storage device. Drag the .hex file to the Micro:bit device and it copies the code over, reboots and runs your code. So simple!

Yesterday we made a simple alarm for Louis' bedroom door. It uses the compass to detect when the door has opened and then fires an alarm. It has a disable switch which involves breaking the banana plug connection on the board. The code itself is really simple and the hardest part was calibrating the compass readings to accurately trigger when the door opens.


Passed my amateur radio license exams

Yesterday I passed my Standard amateur radio license tests. I spent quite a bit of time cramming lots of knowledge in my brain using the video course from the Radio & Electronics School, then took the exam out at the Waverley Amateur Radio Society.

I decided to go straight for the "Standard" license because I have little interest in voice and morse code modes. I want to jump straight into HF digital to communicate around the globe, and possibly play with bouncing signals OFF THE MOON.

The course was really fun. Good revision of my Year 11 Physics (which was a very long time ago, and I didn't really pay enough attention at the time) and Mathematics. Then while working through radio physics, practical receivers and transmitters there were quite a few "a ha!" moments where things I'd always wanted to know suddenly became clear.

In the end the exams were quite easy. You can get 30% wrong, which is pretty lenient, and the multiple choice format means usually two answers are obviously wrong, so your odds can be pretty good even when you're not sure.

It's made me think I should now go for the Advanced ticket. Lots more to learn and I actually really enjoyed learning again.

In 4-6 weeks (why does it take so long?) I'll hopefully be on the air as VK2VSR. See you there.

Notes on the course and Linux

I run Linux and the Radio & Electronics School's course assumed you're running Windows, so here's some pointers.

Ask Ron for the DVD image and mount it. Then uncompress all the video files with (the quotes mean the wildcard string isn't interpreted by your shell, which will not do what you want):

unzip '*.exe'

I converted the video files to mp4 so I could play them more easily on my tablet. I also sped them up because Ron talks very slowly, which might be fine for some but made me impatient. I did that with ffmpeg like this:

for f in *.wmv ; do  ffmpeg -i "$f" -filter_complex "setpts=PTS/1.7;atempo=1.7" "$f.mp4"; done;

The drill software runs almost perfectly using Wine. Just associate ".exe" with wine and you can double-click on them and work through them.

Finally, I created this cram sheet to drill myself on some of the rote learning components. I'm not brilliant at rote learning, so needed to work a bit on this. The phonetic alphabet wasn't too hard for me as I spent my childhood flying around in little planes with my Dad and evidently learned it through osmosis. The rest isn't all that obvious and just has to be crammed in. You could also memorise the frequency bands which are part of the regulations exam, but I just assumed they'd end up being absorbed by my 30% pass margin.

Halloween in Marrickville

Big night in Marrickville. Our area keeps getting bigger and bigger every year. We had a bunch of mates around for the festivities, quick barbecue then out onto the streets to scrounge sweets. Lots of fun and some great costumes. The home made Stay Puffd Marshmallow Girl and the separate Ghostbusters were great!

Open Australia are doing amazing stuff

I've been hovering around the open data movement for a while. I lived in London through the early development of what ended up becoming They Work For You around the amazing NTK-driven London tech scene. I've not actually done anything in the space though. I cheered from the sidelines as a bunch of Australians ported some of the tech to the Australian parliament and have been a heavy user of Planning Alerts. Up to now though, I haven't even managed to make it to the pub meetups. Having kids will do that to you!

Lindsay relaunching his Got Gastro finally drove me along to the Open Australia Foundation's pub meetup. It's so refreshing meeting a bunch of smart, motivated people doing really interesting things in the public interest. Really inspiring and I'm feeling fired up to do some stuff now.

Hot damn this tune will get your toe tapping

John Peel famously took the needle off The Undertones' Teenage Kicks and immediately played it again, it was such a perfect pop song. He was, of course, absolutely right.


I had the same reaction hearing Eli Paperboy Reed's Cut Ya Down the other night on FIP. Theoretically it's a problematic piece of music: it's a take on a traditional gospel song and retains all its fire breathing god bothering ways. It's also a white guy (a Yankee no less!) doing his take on a juke joint jam. But holy crap is it an amazing piece of music. Have a listen.

The Cure: still going strong

I've been to four gigs by The Cure now:

The Cure remain one of the most amazing live bands. Incredible to see them again. Had a fantastic time.


Couple of interviews I've done recently

I did an interview a while back for CMO magazine about the emerging "Chief Data Officer" role. It's out now and you can read it online here.

Seems I'm on IDG's radar this year as someone who likes the sound of his own voice and is handy for a couple of quotes. I also did an interview with CIO magazine earlier in the year, viewable here.

MeasureCamp Melbourne March 2016

On the weekend I went to MeasureCamp Melbourne and it was amazing. The idea with an UnConference is that the agenda gets worked out on the day. Everyone shows up, throws some things they'd like to do up on the board and we get into it.

This event brought together some of the finest minds in digital analytics from around Australia and New Zealand. The talks were diverse and interesting, the people friendly and knowledgeable and the venue just right. A great time was had by all!

I'm pushing for the next one to be in Sydney in September, then we can alternate between Sydney and Melbourne. If you can help organise, that'd be great. First step is to find a venue.

Slides from my sessions

Passata Day 2016

In which we turn 215kg of tomatoes into delicious bottled tomato pulp

Yesterday we did what has become an annual tradition, turning a bunch of tomatoes into passata, a tomato pulp with the seeds and skins removed. We transformed a huge wall of tomato boxes into two 44 gallon drums of bottled passata in one big 8 hour push.

The process is pretty straightforward:

  1. Wash the tomatoes
  2. Blanch the tomatoes in boiling water
  3. Push the tomatoes through the passata machine, which separates skins and seeds from the pulp
  4. Push the seeds and skins through the machine two more times
  5. Bottle the pulp into clean bottles with a leaf or two of basil
  6. Sterilise the bottles in drums of boiling water

At the end of that, we end up with mountains of shelf-stable tomato pulp. Perfect for when you need a little bottled sunshine in the depths of winter.

Of course the tomato gets everywhere and it's a pretty messy day, but lots of fun and the results are delicious and super useful.