Monday, December 31, 2007

A chat with Ben and Pete - Episode 11

FlickrFan, the death of hi-fi and more.

This week we chat about the surprisingly technical Stephen Fry, Dave Winer's new application created using his OPML platform, FlickrFan, experiences with Kubuntu and KDE4, AOL cans Netscape Navigator, booting linux from a USB flash drive, and the death of high fidelity music.

Interesting links talked about in the show:

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Killarney Heights space program

A very entertaining morning - thanks Pete and kids!

On a hot Killarney Heights morning, our intrepid gang of space heroes set out on a mission to launch a rocket high into the air. It was dangerous, possibly even fool-hardy (well, that's what my wife was suggesting).

The video shows just one launch but I think we did six until enough pieces had fallen off that the rocket became unstable in flight and was lost, presumably in a low earth orbit.

Friday, December 28, 2007

Newspapers not for breaking news any more

I remember a time when the morning newspaper had a box, outlined in red, with breaking news that was occurring as the paper was put to bed.

This morning, the Sydney Morning Herald arrived on the doorstep missing one of the biggest stories of the year - the assassination of Benazir Bhutto.

Now, I listen to the radio over night so it felt like the story was quite old by the time the paper came and it was surprising to see no mention of it.

In Wikipedia it is reported on her page that she died at 6:16pm local time, which is 12:16am Sydney time (a bit after midnight). Had the paper's front page been set in stone already?

Was the biggest story in the world the fact that NSW police didn't want a water cannon, or that the PM went to the cricket and didn't seem to enjoy it?

I know it's the silly season, but news doesn't stop and in recent years we've had some really big stories at this time of year, including a tsunami.

For three years I subscribed to Time magazine and there is some value to a publication that shows the news of the past week in a way that lets you get a feeling for what has transpired without any pretense of having the very latest news.

It's hard, (for me), to see the value of a broadsheet daily news paper. Our paper recycling bin is pretty much full of it. Perhaps it's time for a daily journal of opinion and analysis that doesn't pretend to have the news of the day any more.

Wednesday, December 26, 2007

Variable DC regulator V1

I'm getting really sick of those little "wall wart" power bricks for everything. My collection is getting silly, particularly as the multi-voltage ones seem to never quite have all the voltages I want.

My recent purchase of an Asus EEE PC is a good case in point, I imported it from Hong Kong so it has a power brick with a dodgy mains adapter plug on the back of it. This device needs 9.5V DC to charge - none of my existing adapters will provide this - hence this week's mini project.

It's a classic LM317 variable DC regulator in a box with a knob. The circuit is straight from the data sheet here. In my version I have 100R for r1 and the potentiometer is 1K. On the input I have a bridge rectifier so I can plug either polarity in to it without fear. Construction is on a tag board, probably a heatsink and some ventilation holes will be needed but the LM317 is well protected against over temperature and current problems.

I'm calling this project version 1 as it turns out it can't supply the 2.3A needed to charge the EEE PC, still useful for other things, but a version 2 is going to be needed for my original objective. Looks like I need an LM150 or LM138 for that.

Tuesday, December 25, 2007

A call for cheaper public wifi

We're staying at a nice hotel for xmas. The kids and I can't live without our internet fix for even 24 hours - is that addiction?

The internet is available here (Sydney) but only via an ethernet socket and it's AU$30 per day!

While I'm away, it's the Asus EEE PC for me, while my daughter in the next room has a PowerPC iBook running Tiger.

Obvious solution: plug the iBook into the wall ethernet, system preferences, sharing, internet tab, share internet connection over Airport - works really well. (Don't forget to adjust power management to avoid sleeping while plugged in).

While I'm on this topic, why don't cafes have free wifi? I've seen it in one cafe using an Unwired connection. This is presumably a very easy to deploy solution, an unwired (pre-WiMax I think) modem and a wireless router to share it in the cafe. Surely whatever the cost of this to the business would be outweighed by the extra sales to people staying longer to use the internet.

Finally, if we must use a commercial Wifi connection, provided by the same people that provide our home connections (Optus, Telstra) then why can't we log in with the account we already have at home?

Anyway, enough moaning from me, merry Xmas.

Monday, December 24, 2007

A Chat with Ben and Pete, episode 9

The Google Talk Babel Fish and more.

This week we chat about Google Talk's automatic translation service, developer frustration with the Android SDK, Firefox 3 and the large number of bug fixes, the Mac security update breaking Ben’s proxy functionality, Apple legal getting testy with Fake Steve Jobs and Think Secret, SSH configuration coolness, and comparing Windows and Mac vulnerabilities.

If you’re still listening, there’s a treat at the end of the show. We chat about the production and publishing of this podcast.


Thanks Ben for production.

I'll be appearing on ABC Radio National Breakfast with Steve Cannane on Thursday this week to talk about electronic book readers.

Thursday, December 20, 2007

Arduino controller board on a Mac

Having played with PIC microprocessors for many years and had good times with the 16f628, it's been hard for me to jettison that knowledge and move to another chip even though it looks much better.

The Atmel AVR chips are low cost but designed for running code generated by "normal" compilers like good old gcc, rather than the PIC chips that need hacked c or basic compilers that know how to use that banked memory.

I use a Mac and always feel like a second class citizen when it comes to software and hardware for embedded systems. Make magazine featured a little board called Arduino that carries an ATMega168 chip.

It's the fastest "greet postie" to "das blinken lights" joy I've ever experienced.

Here's my list of observations so far:
  • The Arduino is open source so you can make your own
  • I bought the Diecimila for AU$37.50 with it's USB connection
  • Chip programmed with a boot loader so it is re-programmed via serial (over USB)
    • The boot loader is freely available so you can burn it into your own chips
  • There is an IDE for Windows, Linux and the Mac that works really well
  • The IDE for Mac comes with the driver you need for the USB interface
  • IDE has gcc-avr built in
    • It links against AVR Libc
    • Language is most of c
    • Syntax colouring
    • Seems actually to use a c++ compiler
    • Has some useful built in functions for doing i/o
    • Comes with libraries for things like printing to serial (and you can do serial comms to the board in the IDE so that's how you debug)
    • There are third party libraries available for stuff like digital servo control
    • Libraries are installed by simply dragging them in to a folder
  • The board can be powered by USB or a separate supply 6-12V
  • When you compile your source the output, including the intel hex file is dropped into a folder with the source so you can even burn it to another chip with your own programmer
What held me back from trying the Atmel AVR chips is the fact that there's so many of them! Where to start? Well, it seems like the ATMega8 is a good start. All the tools are free and if you have a PC with a parallel port you can make a really simple programmer.

Incidentally, I ordered my Arduino from Little Bird Electronics here in NSW on 9-December and it only turned up today 20-December. I think that's a little slow.

Tuesday, December 18, 2007

A look at Sun's Blackbox

Attended a very nice function by Sun at Darling Harbour in Sydney today to take a look at their server in a shipping container.

Racks are squeezed into a standard shipping container in a front to back packing arrangement. Between each rack are fans with heat exchangers that cool the air by using cold water. So the air flows into the front of one rack, out the back, through the heat exchangers and then in to the front of the next one.

Water is much more efficient for removing heat than air. I note that the standard unit contains a dehumidifier...

Racks slide out for access to both front and back. It's a clever idea and achieves higher density than you get in a normal data centre.

The warm water is cooled either in a building's system or in an external cooler and then it re-circulates. The air flow is a loop inside the box too so it all stays cool when closed.

Applications include things like:
  • Temporary data centre (perhaps for the Olympics or to render a film)
  • Building a data centre in a car park or warehouse (because you don't need an expensive space with false floors and airconditioning)
  • Door stop
  • Paper weight
It's a clever idea, although there must be some consternation about Google getting a patent on the same idea. Sun is a much more interesting company than it was a few years ago, there was a genuine buzz of enthusiasm from staff and customers at the event today.

Monday, December 17, 2007

Django Book 1.0 as an A4 PDF

I've been hanging out for this book for more than a year.

Having just done a formatting pass through it, I can confirm that it's truly a great piece of work. 

I ordered it over 12 months ago and can't wait to get the printed copy in my hands but in the mean time, I've grabbed it and done some basic formatting to turn it into a PDF with a useful table of contents which I present for your download entertainment here.

My reading of the licensing is that this is perfectly OK, and indeed others have done it, but they are in strange non-metric formats and none that I've seen have a useful (clickable) table of contents.

(If I have done the wrong thing, please let me know ASAP and I'll remove it).

I did the formatting rather manually by copying the web pages into Apple's Pages. Must say, Pages is a superb word processor these days and I have no desire to run anything else again.

A Chat with Ben and Pete - Episode 8

Amazon SimpleDB, Google Knol and more.

This week we chat about and viewing long-form videos using flash, VoIP on the iPod Touch, Web services interfaces into databases, the Amazon SimpleDB announcement, KDE4, USB vs. Firewire, “upgrading” to Windows XP, and Google’s unit of knowledge.


Saturday, December 15, 2007

80m loop antenna experiment failure

Just a brief post about some experimentation that has failed.

I've been trying to build a loop antenna for 80m (3.5Mhz) to reduce local electrical noise.

The idea was a 2m diameter square loop built from 1m lengths of electrical conduit. First I built with 1 turn and a 300pF polyvaricon capacitor and it resonated nicely at about 20Mhz. Next went to 3 turns and it seemed to resonate around 9Mhz, then 4 turns and I can't get this thing to resonate at all.

No idea what I'm doing wrong or why this won't work. The family is a little bemused about the structure in the back yard - I tried to pass it off as my version of a Xmas decoration.

I did learn a bit about conduit - there are two main kinds around, electrical and water. Water pipe is designed to carry water under mains pressure so it's much stronger.

Update: Check out Alan's excellent response. I will get back to this project soon.

Monday, December 10, 2007

A Chat with Ben and Pete - Episode 7

Project Blackbox, Songbird and more.

We chat about the world of XWindows on Leopard, Sun’s Project Blackbox, developments in the python based web framework, Django, more wake from sleep problems with the Mac, an iPhone MMS application, the Google charts API, and an amazing iTunes clone, Songbird.

Subscribe or just download.

Sunday, December 09, 2007

Bus driver of the year 2007

What an honour, to be driven by the Bus Driver of the Year 2007. We know because he has it embroidered on his shirt sleeve.

Richard drives a shuttle bus around a local loop that includes some retirement villiages. He's amazing in that he seems to know everyone's name and is completely patient with those who take a while to get on or off.

When I took this shot, he said "this isn't going to turn up on MySpace is it?". I said no, not MySpace.

Sunday, December 02, 2007

A chat with Ben and Pete - Episode 6

Facebook Beacon, Google Maps and more. We chat about routers, Peter’s domain woes, Facebook backs down on Beacon, Google and the FCC 700Mhz auction, Google maps and cell triangulation, offline web apps, an interesting SPAM solution, broadband over powerlines and the Eee PC launch. Golly!

We’re now listed in the iTunes directory. Click here to subscribe directly in iTunes.

Also check out the Facebook group. Click here.


Thanks again to Ben for production.