Homemade Blinky Christmas Ornaments
Last year I decided to jazz up our family Christmas cards with LED power, inspired by this article. While I was totally happy with the cards I sent out, I was wanting something a bit more this year so I've decided to take it one step further and create Christmas ornaments for our family that will be sent with this year's Christmas cards.
I had a few criteria that drove my design for the ornament not to mention I had a very short timeframe so simplicity was important:
1. Have the same shape as a typical Christmas ornament (it is an ornament after all).
2. Lots of LEDs, folks in my family love LED blinky things.
3. Battery powered and last as long as possible on battery.
4. Hackable. I wanted the board to be easily hacked by family and friends that were so inclined.
5. Maximize the visual appearance of the front of the board (no through-hole components), I was also going to put a Christmas message on the front in silkscreen.
After a few hours piecing together the schematic, I was pretty happy with the reChristmasOrnamentsults. Ironically when I went to start the board design I ran into a simple but problematic issue of how to evenly place the LEDs on the round board, being the true geek that I am, I wrote a C# app which you can see in the ZIP file attached to this post. It gave me the x and y coordinates for each LED given the radius, origin and degree. Being late at night when I finally got around to laying out the board, this was a true life saver!
Once I had the LEDs placed, I decided to go back and add some blue and white LEDs on the neck of the board to enhance the "blinky" factor. Skip ahead 4 more hours and I had finished the board layout. I always give myself a day or two after the board is done before I come back to it and QA the layout, saves me tons of time staring at a problem and not seeing it! My QA found several issues and once resolved I sent it off to the boys over at BatchPCB.com for fabrication.
Fabrication typically takes three weeks or more but I was nicely surprised when my boards shipped after only 7 days and being the OCD type I am, I had to assembly one of the boards as soon as they came in the mail. It took me about 3 hours to assemble the first board, I was being overly cautious and deliberate in each solder and relearning how to use my hot air rework station. The total time for the first board included soldering up my homemade ATMega TQFP programming board which I used to burn the Arduino Uno boot loader onto the ATMega chips I had leftover from a previous project. I'll post about it in more detail later, I have a few minor tweaks to make to the design before I think I'll be totally happy with it, but it served me well for this project.
With the boot loader loaded, the final test would be attempting to load a sketch on it using my FTDI cable. To my total elation, it loaded the sketch without issue and my blinky utopia began! I was absolutely filled with joy when those LEDs started blinking away, who knew something so trivial could be so satisfying. I learned a lot with this project and I gained some important confidence in my design and layout skills which should serve me well with my next project.
As for battery life, I've adjusted some of the animations so that I could eliminate having all the LEDs on for extended periods of time and found that I was able to leave the ornament on constantly and the batteries died (the board actually froze) after about 40 hours. I thought about putting in a sleep mode after 6 hours of use or something but I think I'll pass and allow the user to just remember to shut them off, heck those inclined could do it themselves!
Well, I'm giving out the ornaments on Thursday (Thanksgiving) so that friends and family can enjoy them on their trees this holiday season, I sure do hope they enjoy them as much as I enjoyed building and designing them! Check out a video of them in action below!
- Title : ChristmasOrnament
Caption :
File name : ChristmasOrnament.zip
Size : 22 MB
IKEA Lampan RGB LED Light
A few months ago, I saw this blog and video. The gentlemen had hacked a Lampan light from IKEA with LEDs, I was immediately enamored with the idea of building it and giving a few of them to my young nieces for Christmas. I figured they'd be far more excited about a one-of-a-kind light than a few more dolls in the 'ole toy box.
I also wanted to further my design knowledge of PCBs as well as better understand using PWM in AVRs, until this point I'd really only played with my Arduino and a few ATTiny13s. I quickly came up with the following design to suite my requirements.
My Requirements:
1. AVR with at least 3 PWM channels. (I used the ATTiny2313)
2. Super bright RGB LEDs.
3. Warm white light for normal use, not the normal blue hued white LEDs.
4. In-circuit programmable design.
5. Fit in the base of an IKEA Lampan.
6. UL approved power source.
First Version of my Lampan RGB LED PCB
I used quite a few surface mounted components to get the size down.
The lamp uses a single momentary button to switch (you need special drill bits to drill the hole in this thin plastic, trust me, check Harbor Freight for them!) between the colors and the two color mixing modes (one, I jokingly refer to as "light switch rave" and the other a slow color changing mode). My wife absolutely hates the blue hue of normal LEDs, so I knew my design would have to incorporate a few warm white LEDs in addition to the RGB LEDs, thus the 3 warm white LEDs in the middle of the board.
I got the 5mm RGB LEDs from here, highly recommended! And yes, I did use a single resistor for each color, typically a no-no in design, but the trade-off was worth it for me. I wasn't overly concerned with exact color intensity from each LED.
A view of the different modes, from warm white through color fade...
View of the LED modes with the light shade off...
Anyhow, this was a fun build and Christmas was a hit, the family loved them. I've attached the Eagle schematic and AVR Studio files to the post if anyone is more interested in the design.
- Title : LampanRGBDriver
Caption : Lampan RGB Firmware
File name : LampanRGBDriver.zip
Size : 3 kB
- Title : LampanRGBLedSchematic
Caption : Lampan Eagle Schematic and Board Files
File name : LampanRGBLedSchematic.zip
Size : 34 kB
1938 RCA 96T Radio
I finally received my vintage radio today. I had purchased it as a "non-working" radio and really only wanted the wood case for one of my other projects which I will talk 
about later when I get it completed. Anyhow, I couldn't resist looking through all the amazing components and it wasn't long before I started wondering how such a fantastically built radio could be broken... The tubes looked good and it wasn't until I pulled them out to clean them up that I noticed a loose wire which was easily fixed. Well, after an hour and half, I've got the old radio working! I never planned on refurbishing it, now I am thinking twice. It's an all-American, beautiful piece of history and I almost feel drawn to bringing her back to her full potential....more to come....
My new E-flite mCX Helicopter
So I got my early birthday gift from my parents! You guessed it, they got me a new E-flite mCX helicopter! My father and I have always been big fans of anything R/C and these new breed of micro helicopters are no exception. We have been flying the Blade CX and CP versions and after he purchased one of these he knew I would love one too! These should not be confused with the cheap-o toys you see at China-Mart or the like, these are highly sophisticated R/C helicopters, including gyros and proportional linear servo control.
I can't say how cool these things are, they are tiny, weigh 1oz and are really sturdy. I've banged my up quite a bit and it still hovers effortlessly. Each battery charges in about 20 minutes and flies for about 6 minutes, after I picked up a few more of the 110mAH batteries and I can fly for as long as my attention span. These are fantastic for the beginner or pro alike!
And as you can imagine, I've already designed a few PCB boards to enhance the charger and allow me to charge 8 batteries at once. I'll be replacing the existing red LED with a low current 0603 blue 5MA LED. Should help with battery life and cooler look if you ask me!
Adafruit’s Ask an Engineer…
Image curtesy of Adafruit.com
I stopped in last night to the live streamming "Ask an Engineer" over at the Adafruit.com website. I was quite surprised with the good questions and insight into the industry. Found out that I can't find an ATMEGA328 to save my life because the plant in France is being shut down and the workers decided to get strike indefinitely when they found out. Dang those frenchies! Anyhow, the discussion was very intresting and it was quite neat to see the very automated shipping process they have built from open-source and homegrown systems. They gave everyone who was on the chat a 10% off coupon, so I decided it was time to pick up a MintyBoost kit for myself. Have been reading alot about boost converters alot lately and figured the kit would be a nice introduction into making my own. I have some ideas on using a home-grown boost converter and a VFD driver to make my very own VFD displays/clocks/etc.
Head on over next Saturday night at 10pm EST and check out the discussion!
Laying Out a Custom PCB
Ever since I started playing with the Arduino I knew I wanted to get futher into how they worked and even start forging ahead with my own designs. Fortunately there is a fantastic community of folks out there who are more than willing to share their knowledge and even blog about it. I owe the community a great deal of thanks in helping me get up-to-speed so quickly on designing and laying out boards for my projects. I have been working feverishly on a new project which I'll dedicate a whole category on here for later. It's really going to be a neat project and I think it's a great way to give back to the community by relasing all my work for anyone to use. Anyhow, more on that later.
EaglePCB, how can I say it. It's freaking amazing. Who could ask for much more with a freeware PCB board layout program? I'm actually in the process of purchasing the Non-Profit version so I can build bigger boards. That being said, the freeware version will do everything the paid version can do but is limited to double-sided boards and limited board size. It really is a neat program and definitely helps people get started with PCB layout cheaply.
For now I wanted to share with the community just one of the boards I've finished and am awaiting arrival of the fabricated board. I released it to get feedback and hopefully help somone else out. It's taken from the Boarduino concept from AdaFuit.com. Basically it's a very basic USB powered Arduino board which can be integrated easily into other projects. I'll be using this board on my new project. I'll warn you of this, I haven't received the fabricated boards from BatchPCB.com yet and tested them throughly so you've been warned. You'll find the board and schematic in the attached ZIP file. I've used parts for the SparkFun.com library. None of this would be possible without those fantastic guys!
Please, I encourage feedback on this design!