Introduction: Aurora 9x18 Kit

About: I am an electronic artist living in Upstate New York. I work with LEDs, microcontrollers, and analog electronics to create objects that I find beautiful.

*** There's an updated version of this kit available at http://www.theledart.com/blog/store ***

Responding to many requests, Aurora 9x18 Kit is now available, so this is the Instructable specific to building the kit.

Please leave comments, especially tips for successful assembly.


Step 1: Identify the Parts

First, identify all the parts contained in the kit.
Below is the parts list.

[Parts List]
qty item
   1x Custom PCB
162x 150Ohm (0603)
    9x 220 Ohm (0603)
    3x 470 Ohm (0603)
  13x 1k Ohm (0603)
    1x 10k Ohm (0603)
    1x 1uF (0603)
    2x 10uF (0603)
    1x AP7333-33 or AP7313-33 ("JZ" or "NZ" printed on it)
    1x PIC24F08KA101-SS
    3x DMP3098L ("DMB" printed on them)
  12x MMBT2222A ("K1P" printed on them)
    1x 4-way Stick Switch EVQQ7
162x Tricolor LED (common-cathode)
    1x Molex 2 pin header (right angle)

Resistors have their values written on them. Two top digits followed by the number of 0's after. So 150 ohm would have 151 written on them. Those are so small, be careful not to misplace them. I always tidy up the work area before starting assembly. Make sure you have a good lighting, too.

Capacitors do not have anything written on them, so be sure to keep them in the carrier (tape) until you are ready to solder them.

Transistors have letters printed on them, however they are codes, so the codes are noted on the list above.

Other parts are quite obvious, I think.


Step 2: Tools & Supply

  • Magnifier visor or other visual aid device (I think this is essential)
  • Tweezers (fine tip ones)
  • Solder paste in syringe*
  • Electric hot plate*
  • Soldering iron (temperature controlled)
  • Solder (flux core. go for the highest quality solder you can afford. 0.015 inch / 0.4 mm diameter recommended for SMD.)
  • Solder wick (thin braid recommended - mine is about 1.5 mm wide.)
  • Wire cutter (I recommend this one.)
  • Microchip PIC programmer (supports PIC24F08KA and capable of In-circuit programming through a standard 6-pin ICSP connector, such as ICD2, ICD3, PICKit2, PICKit3) and a computer

(* If you are doing the reflow method)

Good lighting is also very important. You can work much better when you can see the details.

Step 3: Solder the SMDs

I've shown the "poor man's reflow" method using solder paste and electric griddle on the Aurora 9x18 Instructable. You can do the same, however hand soldering is still a viable option. I think hand soldering might be quicker for more experienced solderers.

* I don't recommend Aurora 9x18 to be your first SMD project. If you have not done any SMD soldering before, please practice before taking on Aurora 9x18.Aurora 9 bar might be a good project to get your feet wet.

There are so many videos showing the SMD soldering techniques on YouTube. You might want to search "SMD soldering" and watch some. You will realize that SMD soldering is nothing to be afraid of.

(This one is very informative: http://youtu.be/3NN7UGWYmBY )

Print out the part placement guide (ideally in color) and follow the order to minimize the errors.


Step 4: Inspect & Program

Once all the SMT parts are soldered, inspect carefully for bad joints and shorts.

After making sure everything is good, it's time to program the PIC microcontroller. This part is described in the step 10 of the original Instructable. However here are the points:

  • Connect 5V power supply - you can not supply the power from the programmer, as that will stress the voltage regulator on board.
  • See the chart for the pin assignments.
  • 6th pin of the ICSP connector (LVP) is not used. Use only pin 1 - 5.
  • You need to use "High-Voltage Programming" mode, in order to write all of configuration bits required for Aurora 9x18. You will find this option in IDE, under "Programmer" menu -> "Settings". On "Program Memory" tab, check "Use high voltage on MCLR".
  • If you are using older programmers which output higher than 9V to program (like ICD 2), please add a voltage limit circuit to protect the PIC24F used. See the photo with my comment.
  • PICKit 2 and 3 are fine without any modifications.
Download the HEX file and program the PIC.

If you get the following:

"The following memory regions failed to program correctly:
Configuration Memory
Address: 00f8000c Expected Value: 0000007a Received Value: 000000fa
Programming failed"

then you are not using high-voltage programming mode. Please double check the setting (see the screen shot) and try again.


Step 5: Solder the LEDs

Here please refer to the step 12 of the original Instructable.

Take time doing this step. LED pins are very close together, so you might have to use solder wick often to clear the solder bridges. Also, use of high-quality flux is essential here. Use pen tip or small brush to apply flux to the pads and leads.


Step 6: Power Supply

I made it seem like the power supply needs to be heavy-duty, however that's not so. I find just about any regulated 5V power supply of 1A or higher rated current to work fine. Some AC adapters of only 500mA rated capacity work just fine also.

Right now my favorite is USB power supply (often called USB charger). I've made a USB power cable (picture shown), and tried all USB power supplies that I have. All of them work, except the lower capacity ones (500mA) do dim the LEDs a bit. 1A rated ones are just fine, and they can be had for very cheap.

Taking power from computer's USB port is not recommended. (Although it works with my computers, Aurora 9x18 doesn't "ask" for high current using proper USB protocol.)


Step 7: Good Luck and Enjoy!

Hope you've built your Aurora 9x18 successfully.

Let me know if you have any questions or suggestions.