A brief foray into explosions

Every year, myself, my family and some friends get together on New Year’s Eve, have a lovely meal and at midnight, let off the obligatory fireworks. Their house is surrounded by farmland so we have a huge amount of space, making operation of larger fireworks possible, but we’ve in past years stuck to firing the larger end of garden fireworks (category 2).

This year, tired of the inevitable mucking around with unreliable gas lighters at midnight, we decided to take a look at electronic ignition systems and upgrade to category 3 “display” fireworks. Continue reading A brief foray into explosions

Broadcast-quality OBs with Raspberry Pis

OpenOB‘s been ticking along nicely but it’s historically needed a bit of oomph and capital in the form of two computers running Linux. This isn’t often what you’ve got on your PC and it’s not something you can easily chuck in your reporter’s rucksack to take along to an event.

This limits its usefulness somewhat. So what you need instead is something cheap, small, and lightweight, that can run Linux and do everything you need it to with regards to OpenOB and network management.

Enter the Raspberry Pi, the £25 wonder-SBC. It’s got audio out (not in), runs Linux off an SD card, is small, runs off 5V power supplied via USB, and did I mention it’s £25? Okay, £30 if you buy from Farnell with shipping thrown in, and probably more like £60 when you’ve bought a power supply, sound card, SD card, etc. But we’re still talking an outside broadcast remote and receiver for a grand total of around £200. Compare that with the £1,500 per end of the current cheapest commercial solution, or the £5,000+ an end and up boxes found in most professional OB trucks. Sure, you don’t get their slickness or polish or even all their features, but you can move audio and you can do it well with OpenOB. With Opus, now from 16kbps all the way to 384kbps or linear PCM.

The primary OS supported for the Pi is Raspbian, a Debian derivative, which is awesome – because Debian/Ubuntu is the standard platform on which I develop OpenOB.

So can we actually make this perfect storm come to pass?

Update, 3rd Apr 2014: This post has been superseded by the OpenOB documentation. Please don’t try and use this post to configure your Pi – it is wrong in places as a result of updates and is not being maintained.

Continue reading Broadcast-quality OBs with Raspberry Pis

Getting airborne

Last week I got paid! And immediately blew a hundred quid on parts for the UAV project.

I’ve already got an airframe, speed controller, and a Turnigy 9x TX/RX pair. Unfortunately the Turnigy is bust (thanks, China!) so I needed a better solution. Rather than go crazy and buy an expensive RX/TX paid I decided I’d roll my own solution using some off the shelf parts. The core of this is a board from Adafruit which will drive 12 PWM or servo outputs from I2C, plus a Raspberry Pi SBC and an XMOS XC-1A development board. Continue reading Getting airborne