DIY Ghost Buster Pack LEDs!

    My friend Oscar asked me if I could help him with the electronics for his "Ghost Buster" Halloween costume this year. His vision was to recreate the original proton packs from the movie. The circuit would simply turn the four red lights on the back of the proton pack on and off in sequence. This would also include a power switch and a knob to control the rate of the blinking LEDs. I started by searching the web for LED circuits and the first thing I stumbled upon was great website which turned out to have a large resource of free circuit designs. I found an LED Chaser circuit that could control the LED sequence. The circuit combines two IC's (integrated circuits) a 555 timer chip and a 4017B CMOS decade counter. Most of the materials and parts you'll need to build the chip can be found either online or at your local electronics store(RadioShack, ect). To build a prototype on a breadboard you'll need a few resistors (1K, 10K), a 2 10uf capacitors, a 10K-500K potentiometer, 11 LEDs and lots of wire.  Below is the circuit design for the LED chaser from www.elecfree.com.

    We started off by building a prototype on a bread board. This step is easy just follow the diagram and make sure that all of your connections match the circuit above. Once we tested the chip on the bread board we were ready to design our PCB (printed circuit board). Oscar found a free multi-platform application online for designing and testing PCB's called EAGLE. The program is easy to use and comes with a library full of parts to use. You simply select the parts you need, lay them out and wire them together. Export the final board from EAGLE as an image file and print it out on a laser printer. If you don't own a laser printer you can always go to a copy store. Because the etching process is much more involved I've written a separate tutorial on the blog showing you the process, here (DIY PCB etching).

    If you'd rather skip the etching process and you just so happen to be a fountain of patients you can solder the parts directly onto a pre-perforated board. To do this you have to have a clean work space and the right tools. Soldering this board took me around 4-5 hours but I imagine with a little more practice I could have it done in about half the time.

   In this video you can see as I turn the potentiometer controlling the 555 timer's pulse i'm also changing the rate of the blinking LED. The although the 4017B(the larger chip on the board) is not hooked up in the video it does function and can sequence up to 10 LED's at one time.

 

DIY PCB - Etching your own (Printed Circuit Boards) at home.

    Here's a quick tutorial on etching a custom PCB at home. All of the materials can be found at your local electronics store or online. Here is what you'll need to get started.

MATERIALS:

sodium persulfate(toxic stuff)

1 sheet of copper clad board(also pretty toxic)

acetone, rubbing alcohol and cotton balls

glossy photo paper

1 sharpie marker

TOOLS:

3 plastic containers(got mine from ordering won ton soup)

1 rough side of a dish sponge or 1 sanding block

 laser printer(or access to)

ironing machine

Dremel or small hand saw

PCB Software (EAGLE)

(CAUTION) 

The materials use in this tutorial are toxic, dangerous and even deadly if not handled properly. Make sure to wear protective gear and to work in a well ventelated space. It's a good idea to wear gloves and a paper mask while following these steps.

GETTING STARTED

    We are going to start out with our circuit already exported from EAGLE, the software used to draw the circuit. The first step is to print your circuit design out on glossy photo paper with a black and white laser printer. Next cut the design out leaving 1/4'' boarder around the outside.

CLEANING THE CLAD

   Cut the copper clad down to the size with a dremel or small hand saw. In order for the ink to transfer correctly to the copper we must first cleanse the surface of any oxidation. Use a rough sponge or a sanding block to remove the first oxidatized layer. Scrub firmly until the entire surface is lightly scored. Use the rubbing alcohol to remove the first layer of grim left behind from the sanding. Use the acetone and remove any excess rust or dirt that may be left behind. Clean until there is no more dirt transferring from the copper to the cotton swabs. Once the surface has been thoroughly cleansed be very careful to not touch the surface again with your hands.

TRANSFERING THE DESIGN

    Turn your iron to its highest setting. Lay the printed design face down over the copper  side of your chip and sandwich everything between a sheet of wax paper. Once the iron is preheated place the iron on the chip and apply at least 40lbs of pressure for a minimum of 30 seconds. Then use the iron tip and continue to put pressure until the paper sticks to the chip. after the chip cools down a bit dunk it in cold water. After a minute take it out and peel the first layer of paper off. Put the chip back and let it soak for another 10 minutes or so before taking it out again. To remove any excess paper, rub the surface with your thumbs or use a soft tooth brush. Inspect the transfer and make sure all of your connections copied over correctly and that no residue left behind from the paper. If you did not get a good transfer start over from step one. Some errors can be fix by drawing over them with a sharpie marker.

 

ETCH-A-PCB

    Alright here comes the fun part. Preheat the sodium persulfate by placeing the container in a bath of warm water for about 5-10 minutes. Place the chip in a container and pour sodium persulfate over until the chip is just covered. Agitate the container constantly for the next 15 minutes or until all of the exposed copper has been dissolved away. Take the chip out of the solution and drop it into a seperate container of cold water. Dry the chip and there you go all that's left is to drill the holes and soldering on the parts.

 

Big Brown Table releases new video!!!

Todo Muerto is complete and coming soon to a television station near you. Shortly after the release of Los Telecasters new album Todo Muerto, Big Brown Table announces the release of the bands latest video. Check it out! If you like Los Telecasters here's a link to their website. http://www.lostelecaster.com