I have to agree completely that the faire was once again great.  It was great seeing how the exhibitors projects had developed, including yours Grumpy_Mike.

I put a short video of the weekend together on the train home.  It should hopefully give you a taste of what was going on if you were unable to make it.

As for running fast I haven't left my set up on long term yet so I'm not sure if I see the same issue.  I'll try and remember to leave it running tonight and see what happens.

I've just got around to checking this.  I've powered up my arduino board and the error is less than a minute after leaving it for at least a week.  I can't remember how accurately I had it set to begin with but any error seems to be small.

This is amazingly similar to the process I'm currently going through.  Only difference being that I'm using a breakout board from sparkfun for the DS1307/crystal/battery combination.

My understanding was that there are inbuilt pull up resistors on the pins used for the wire protocol so additional resistors are not needed.

As for running fast I haven't left my set up on long term yet so I'm not sure if I see the same issue.  I'll try and remember to leave it running tonight and see what happens.

I would be curious to hear what you're working on.

[edit]Just for reference I'm using this product though I don't remember paying that much for it.  :-? [/edit]

You need one (or a few) BuckPuck LED drivers.  They are dimmable (voltage controlled or PWM) deliver constant current regardless of input voltage and are available with pins or leads.  I use these for all my power LED projects.  They are very easy to work with.

http://www.ledsupply.com/buckpuck.php

They do indeed look very easy to work with.  It looks as though dimming is achieved by reducing the current rather than with PWM though which would limit the range over which dimming would work.

Thanks jluciani and Grumpy_Mike, I'll give the SMD option some consideration.  

Grumpy_Mike, you may already know but your PWM tutorial is lacking files - http://www.thebox.myzen.co.uk/Tutorial/PWM.html

I had thought that soldering SMD components required a reflow oven and all the associated equipment.  I would guess that it would also need a custom circuit board rather than using stripboard which would either require additional equipment or push up the price if I used one of the online services.

I fear you may be right but I hope you're wrong.  

I'm planning to build a fairly large array of LEDs, to a total power of ~5 W, the brightness of which I want to control with an arduino.

If it was just one LED I would just connect it straight to one of the PWM pins on the arduino through a suitable resistor.  For something slightly larger I would throw a transistor in as well but my understanding is this would still be unsuitable for something of 5 W power.  From other posts I've read on this forum and elsewhere I need to use an LED driver which will limit the current.

I've found quite a few drivers but they don't all support dimming.  Quite a few of the Linear Technology LED drivers do support dimming but they only seem to be available in SMD packages.  My soldering skills aren't really up to the challenge of soldering SMD so I'm really looking for something in a through hole package.

Does anyone have any suggestions?

The other way if I remember.  Next to the building mathematics group/display.

Craig, That's great.  Welcome to the community.  

Mike, I'm glad it went well for you.  It was good to see more stands and the event growing.  There can't have been much less space; there were more stands but it was also in a much bigger space.

I went around a couple of times and on each occasion there was someone by the door to the marquee and at the base of the ramp leading to the inside area checking tickets.

There were a few things going on outside which were free.  That might be what the flyers were referencing.

I went down to Newcastle yesterday and had a great time.  Arduino was in use by several of the exhibitors which was nice to see.

I've thrown up a short writeup and video of some of the exhibitors on my site.

This sure has come around fast!

I'll probably head down for the Saturday like last year.

I hadn't realised they were charging for entry this year.  I don't suppose I can complain too much about 4 quid though.

I'll definitely try and make it again.  Thoroughly enjoyed it last year.  

Looks like I'll be spending two weekends running in Newcastle as there is a BarCamp event the very next weekend.  I should probably get a move on and finish the project I'm working on.

TonyD:  That would be good.  Last year it seemed as though every other stall was involved in Arduino in some way.  It would be good to add to the mix.

You're welcome.  I enjoyed the day and it was nice to see so many groups using Arduino.

I hope Sunday went equally well.

I'll find you during the morning and we can discuss when you would need some help.

With regards to the shield page it works fine for me as well.  I just wanted to make you aware of the typo.

You wife would be right to ask.  My best guess is they couldn't decide between fair and fayre and decided to meet in the middle.

A few posts ago you asked if anyone was available to help on the stall.  I would be willing to help out for a few hours if needed.  I have almost zero experience but I'm willing to bring my naive and misinformed enthusiasm.

They've now got details up for the stalls: http://makerfaire.com/newcastle/2009/makers/
You site actually looks more professional than the site for the "2009 Fighting Robots UK Featherweight Championships"
Check the url for this page though: http://www.thebox.myzen.co.uk/Hardware/Arduino_Sheld.html

The Newcastle Science Festival website is now live: http://www.newcastlesciencefest.com/

Maker Faire - Saturday: http://www.newcastlesciencefest.com/Events/Details.aspx?Id=67
Maker Faire - Sunday: http://www.newcastlesciencefest.com/Events/Details.aspx?Id=68