Monday, March 26, 2007

Apple TV arrived in Sydney

My Apple TV just arrived here in Sydney.

Not much I can say so far except the box is pretty nice. It shipped on the 20th and just arrived now, a bit longer than expected.

Later: Now that I've got it going, here's my impressions:
  • Very easy to set up, booted, on the network, shows a number that you key into the iTunes you want to pair it with.
  • By default it started syncing all my Music. I didn't buy this thing to play music on the TV so I've changed that default.
  • iTunes immediately tried to sell me music videos, which is about all there is in Australia at the moment, I fell for it and bought a few clips.
  • The TV trailers are tantalising, Lost, Grey's Anatomy, etc etc. Of course we can't buy any of these in Australia. Grrr...
  • The interface lags a little but probably because it was madly trying to sync my music library.
  • Visually, looks lovely.
We don't have cable TV and I'm prepared, keen in fact, to spend the money that would have gone on cable, on purchasing shows I really want to see.

  • It doesn't play everything I can play in iTunes. Not sure why, I've got a quicktime movie in my library that won't sync over.
  • Some videos, including movie trailers from Apple lose their Video/Audio sync pretty badly.
  • iTunes kind of forgot about my iPod for a while. Had to re-boot the iPod, seems ok now.
  • They need a black version, after all, most flat screen TVs come in black.
  • Why doesn't the volume control work? The nifty remote control only has 6 buttons and two of the don't do anything.
I'm happy with the product and very much enjoyed watching video podcasts in bed last night. Can't wait to buy a TV show or movie.

Home brew meeting at Dural

On Sunday I attended a technical meeting of the NSW home brew radio group. Steven, pictured gave an excellent demo of some of the the metal work skills needed to make chassis to hold projects. So many things I don't know. Some more pictures.

The meeting was held at the WIA Dural site, where they do the NSW Sunday broadcast. I've listened for many years on Sunday mornings so it was great to have a look around.

I got my amateur license back in 1978 with a group of friends, after moving to Sydney and finding that the internet has become my main form of communication, radio faded for a while but since the dropping of the Morse code means I can use HF I've come back and feel more interested than ever, in particular I'm keen to learn to make HF circuits.

Sunday, March 25, 2007

FatBlog 75.4

A few years ago I returned from living in Hong Kong to find that my weight had crept up to 82Kg. Amazing how this can happen without noticing. I did feel bad and bloated.

My workplace had a few people in the same boat as me and kindly they organised a weight loss program that worked very well for me. I lost 10Kgs, mostly by replacing snack food with carrots.

Once again, my weight is creeping up so about ten weeks ago I started trying to lose some weight again. I record my daily weight in the morning. Above is a graph of my weight once a week on Fridays. (I'm being kind to my self as I always go up over the weekends).

Things I've learned about losing weight:
  • Can't do it by starving, hunger is a very strong drive, you might beat it for a while but it will win.
  • Can do it by replacing one filling food with another with less energy in it. I lost 10Kg by eating lots of carrots.
  • Can do it by stopping eating when you are satisfied. (It's a real trap that you'll finish the whole plate just because it's there).
  • Exercise makes me hungry and may not result in weight loss.
  • Exercise needs to be sustainable, I know if I join the gym I won't keep going in the long term. Walking on the way home, however, seems sustainable.
  • Don't worry about daily fluctuations. Actual weight is mostly water and that goes up and down often by 1 or 2 kilos. Track weekly results and don't panic if one day goes the wrong way.
I'm not going to blog on my weight very much but hopefully this post will shame me into staying focussed.

Wednesday, March 21, 2007

Apple TV shipped!

Got an email over night that my Apple TV has shipped. I ordered at 5am local time, on the morning they were announced so I guess I'm at the front of the queue.

What's the best way to convert DivX to H.264....

Friday, March 16, 2007

Improving construction and the nature of blogs

It goes without saying that blogs are a diary and the writer moves on as they write. For some reason I'm interested in learning how to make things. 

Tonight I re-made a crystal oscillator built a few days ago, as you see it's more compact and professional looking. (They both work by the way).

I'm on a learning path and happily there are wonderful folks out there who have selflessly shared their knowledge. I'd like to pay tribute to a few generous people I've come across:

And many others.

There's a few things that mystify me in constructing electronics:
  • Capacitor markings
  • Winding inductors
  • Complex numbers (although my daughter seems to understand them)
I'll get there...

Monday, March 12, 2007

Manhattan pad construction

I've been trying to find a way to make one-off electronic construction projects. After a few false starts this looks like one I can get good at. It's known as "Manhattan Pad" construction method.

The circuit is built on top of copper board, unlike "ugly construction" components are joined by soldering them to little pads of copper board, cut up and super glued on to the base board. This makes it much easier to solder component by component for those of us who don't have three hands.

Here is my first go, a simple VFO that covers 3-4Mhz. Once in a nice box with connectors on the outside you'd never know it wasn't a professional job. Having the components close to a ground plane helps with RF stability too.

Apologies for my tiny steps, hopefully I will get on to more interesting projects soon.

Sunday, March 11, 2007

Radio New Zealand (RNZI) back on DRM

Just noticed that Radio New Zealand has started transmitting digital radio using the DRM system again. It's the best DRM signal I can get here. So far very patchy decoding for me, the picture to the right is about the best signal I've got so far.

My receiver is a DRT1 controlled via serial from the Dream software.

As I write (approaching 6pm AEST) the signal is improving and I'm getting a signal to noise radio of 20dB sometimes which gives perfect decoding.

Update: It's 9pm AEST and I'm getting perfect decoding with 28dB SNR. Changing "Time Sync Tracking" to "First Peak" seems to improve things for me.

Saturday, March 10, 2007

Ham radio Sydney to Melbourne

I've had a ham radio license since 1988. Never managed to learn morse code. I'm vk2tpm.

Now that morse code has been dropped I have an advanced licence and can use HF for the first time, very exciting. 

New to all this but basically it means you can talk to people about 1,000 km away. I'm from Melbourne and moved to Sydney about 20 years ago so I'd like to talk to my friends there. 

Dave, vk3ase, has a regular test transmission on 3.670Mhz AM on Saturday night. 

It's very strong here, a solid S9, but there's a lot of band noise tonight. We had a bit of a chat of SSB but it wasn't easy going, mostly as I was switching between SSB and AM and messing things up along the way.

By the way the IC-7000 is the best radio I've ever used.

A week without the internet, at home

Last weekend we had an electical storm. I unplugged all the radios but forgot about the cable modem. It died.

It took Optus 5 days to send someone out. They gave me 12:00 - 5:00pm as a time range, couldn't ring first or anything, so I had to stay home waiting for the guy to come. He turned up at 11:30.

We had five days without internet at home. Amazing the impact. I read the newspaper, it's not as good as reading RSS feeds, but not bad. Over priced if you ask me.

The kids were distraught. They basically said that they couldn't do their homework without the internet. 

We also lost an ethernet switch and the ethernet port on a Mac Mini.

Sunday, March 04, 2007

Software defined radio (SDR) is totally cool

I got into this via my interest in digital radio. Computers are now fast enough to do the processing required to demodulate radio intermediate frequency in real time. 

You can therefore have a very simple bit of hardware radio frequency down conversion that feeds into the audio port of your computer and the rest is done in software.

SDR gives you an incredibly full featured radio, with more dials and displays (all virtual), than you could want. I've been aware of GNURadio for some time, but it's pretty hard to get started with.

There is even software for the Mac from the incredibly friendly Kok Chen (with source!). I notice that hamlib builds just fine on the mac and the command line tools work. This means you can control many "hard" receivers via a serial port (works with USB adapters). So far I haven't found a nice cocoa client that uses hamlib so I'm working on one myself.

I paid rather too much money for the nifty DRT1 from Sat-Schnider and have spent the weekend playing with software and mounting it in an external box. This thing is controlled by commands over a serial port (it has no display at all - I've added a power LED). It converts a slab of radio down to audio which you feed into your computer for demodulation.

There are several software radios around, the one shown above is from Peter Carnegie, but there's also the Dream software for DRM decoding.

Seems to me that this kind of thing might be built at very low cost using an NE602 balanced mixer and synthesized oscillator controlled by a PIC microprocessor or something.

I heard today on the WIA Sunday broadcast that the BBC is to begin trials of DRM (Digital Radio Modiale) on medium wave. Perhaps radio is set for another revolution, AM -> FM -> DRM.