Tuesday, October 1, 2013

A DIY Led Light Bulb, Courtesy of theledart.com and oshpark.com

Purple looks good on green, doesn't it?
I'm an avid listener to The Amp Hour and they interviewed the guy behind OSH Park.  @Laen was a heck of an interview, and made me want to try out his service.  But my circuit drawing skills are, well we'll say, lacking.

I also hang out on IRC, and one day, in #electronics, someone posted a link to this: http://oshpark.com/shared_projects/s4fzpaFO  I needed it.  It was just to clever not to have a copy of my own.  A few minutes later, I had an OSH Park account, and had ordered copies of the board.  

The circuit is really simple, and easy to follow.  It's a bunch of leds, a bridge rectifier, a big cap, a couple of current limiting resistors, and a resistor to make sure the cap discharges.  I could guess at the design values... and had already decided on what I was going to use, but, I thought it might be a good idea to contact the designer.

The designer of the board, is a seemingly prolific electronic artist, who turns out some really neat LED projects.  His site is: http://www.theledart.com/blog/  Aki was a big surprised when I contacted him, but was happy to help.  He sent me a copy of the schematic that he built the circuit from.

A few days later, this showed up at my door:

My friends and I were wondering if I would need to trim the board, turns out that the solid black line is a routed line.  Not a bad looking board?

As soon as I had the schematic from Aki, I went and ordered the right parts.  But I couldn't resist putting int he parts I had on hand.  
You don't really grasp how many solder joints are involved in a 48 led bulb until you need to start trimming the legs off.
I didn't ask Aki how he did the hookups for the light socket, I suppose I should have.  Here's what my bulb looked like after getting my contacts in place, and all the LEDs soldered in.  
And since I'm silly, I ordered most of the finishing parts from Chinese suppliers.. it was another week before I could finish the board.  Here's the final product:

Oh, and I did a little video of the project too: