Robvdveer

All this is probably why a PF light costs around €8. I bought 50 hibright leds in China with resistors and heat shrink for €5 incl. P&P.

I'm sure there are situations where the leds have some kind of built in resistor, but that's not common. Not everybody knows how a multimeter works and how electronics work, so the basic advice still stands: Just use the resistor unless you know what you are doing.

Always use a resistor when lighting a led. Without, it won't burn your hose down, but your batteries will be flat instantly, and the led will be ready for the trashcan. It's not difficult, just get a good tutorial from google or youtube..

Hi Ole, I dd put up a little tutorial earlier on fitting the lights, i don,t know if you saw it: http://simplicate.weebly.com/1/post/2013/05/about-adding-led-lights-to-lego-technics.html And there are massive amounts of tutorials on the internet about electronics and soldering. I especially liked the tutorials at www.sparkfun.com they range from basic soldering all the way to creating custom PCB's.

Thanks, leoparder What a coincidence! I'm planning to write down a little story on the software side of things tomorrow. Check my blog for updated! (If i don't forget, i'll put up a notice here as well),

Hey that could be my next project! I'm also very eager to see what possibilites the August '13 models will bring.

Just awesome

I very much like your work! Looksgood and interesting read!

That's putting it very simply. There is also the animation and controlling of those lights, reading/decoding infrared signals and bluetooth communications. All crammed into very tight spaces. I'm pretty new to electronics, i could have used even smaller SMD components or purposeprgrammed PIC pricessors to get it to about 25% of its size. But SMD soldering is a little too advanced for me.

Thanks Horace, but i'm not sure we understand eachother. I'm using the standard lego powerfunctions battery box, but with rechargeable batteries inside. This has several more aH's (amp hours) than a regular 9v cell. I cut a PF extension cable and connected it to my board and lights.plus i keep the originality of the model and the exsting power functions.

I'm finished. Well not really, i need to clean up wires etc. But all the lights are connected. With all lights on, a fully charged PF battery pack with rechargeable AA's is empty in 2 hrs. But it surely lights the room up! I'll be monitoring battery usage in the coming weeks, perhaps i can squeeze out a little more. Also, i've been looking to have a proper PCB produced, perhaps with some lego-sized holes for mounting. That would be cool for a 2nd version. This weekend i plan to update documentation and upload a video of the features. What needs to be done? Cleanup, as mentioned, and the software isn't finished, it cannot be operated remotely yet. Perhaps add feature to dim the lights so the battery holds out longer.

Awesome! you know i'm jealous on the amount of space you have in the Unimog. Remember, to get a perfect flat fit, grind of the rim of the led, like the marked bit in the image below. I used a small electric knife sharpener to do that, but any dremel-like tool will do. Then you can push the leds all the way in (incl. a bit of wire). Also make sure you select the right leds, i used high intensity, 25 degree beam leds.

Thanks so mch, Ole In other news: here's a closeup of the control board installed in the proper place:

If you use a half-connector with 3mm leds, you can click the leds almost everywhere. http://www.brickset.com/parts/?part=4211483

Almost done!