Happy hacking with HP LEDs

Last Thursday 6.2.2014 I noticed on #helsinkihacklab irc channel some talk about happyhackingday.org and noticed it is pretty soon, the then next tuesday, and it seemed pretty interesting. I naturally decided to go and join the hacklab team.

Come tuesday I drove to Helsinki Hacklab to pick up some nice 20W LEDs and headed to Pasila with the huge bag of nearly unsorted goodness (we need a pre-prepared demo kit). At the site some friends were already assembling the nuclear reactor and told me I’m allocated a slot right next to it, so all things looked bright.

I unloaded half of the goodnessbag and started to piece together a small demo of an ethernet powered light fixture featuring a high efficiency DC/DC converter controlled by software instead of a SMPSU chip. The scope proved that a switch mode power supply without filter caps rings badly and it looked fabulous on scope screen. Adding the cap made waves look nicer but the drama was gone, so I left the cap out. The circuit looks like this: https://github.com/Ell-i/Hackathon/wiki/LED-driver-forward-control-testing except I had a 20W LED instead of that huge resistor, and C1 was nowhere to be seen.

During the set up people started to trickle in and from that point on I spent the rest of the day chatting about ELL-i control system, its story, technology and all with huge amounts of people. I had also some time to pitch the Hacklab reactor and people had a blast trying to adjust carbon rods to maintain power output. The thing smoked a lot and blew up repeatedly but as my bright LED soldiered on, I was not worried a bit.

https://www.dropbox.com/sh/lsnt45xvh695q54/qEDlG_g-g0/DSC_0347.JPG?m=1

There were supposedly some speeches in the auditorium, but nobody had any kind of schedule anywhere and I was busy chatting people up and pitching interest in embedded systems development and all that. I missed Richard Stallman, which is a shame, even though I know his message pretty well, having used Free Software and Open Source Software. I’m more on the OSS side and actually like BSD/MIT licencing more. Anyway, some other speeches I missed too, but they are local so that can be fixed. Go see windytan.com for some new old school hackery.

Anyway, all in all, a very energising day full of nice chats and interesting people, thank you and see you next year.

– Teemu