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breadboard card reader

card reader

Alright so after the CMoy amplifier I set about for something more fun. I stumbled upon an open source program called Stripe Snoop I quickly bought a Omron V3A card reader from digikey and set about hooking it up to my mac book via USB. The card reader comes with no wires attached and then you have to pop open the sides and either connect a really tiny hard to find molex connector or there are pads in front of the pin connector that you can solder directly to. So I decided to just solder directly to the pads. But first I needed to create my cable. I decided that since this was going to be something to play with that I wanted to be able to connect it to my breadboard, so I went out and bought a DB9 connector. I used all the individual pins to crimp onto the wires and make something that would fit into my breadboard easier. Then all I had to do was solder up the wires and snap the case back on. It worked great! I hooked up some simple LEDs to the card detect pin and PWR and GND and could swipe cards and light the LED. The next step was to wire it up to my AVR micro and then connect the AVR through my FTDI 232 breakout board to my laptop. Well I connected that all up but so far have been to lazy to write the firmware to get it all talking together. Just one more thing on my list of things to do.


So for my second project I picked something to work on my soldering skills. A cmoy headphone amplifier seemed like a good choice. I managed to find a great web site explaining how they work and different parts I would need. Definitely check out “How to Build the CMoy Pocket Amplifier”. The tutorial made it easy to build. The hardest part was soldering all the connections to the switches and input jacks since I don’t currently have a third hand tool to help me hold stuff so it can get pretty tricky. Anyway here’s the result.


It sounded great and was loud enough that when I plugged in a crappy pair of earbud headphones and cranked it up it sounded like a set of speakers. Unfortunately I used solid wire which made the bending of the wires really hard and I was not able to shove it all inside an Altoids case. Either way it was a fun project and I figure I can probably re-use the potentiometer and switche in other projects. 

breadboard, power supply, microcontroller

So my first task was to get a breadboard, because how could I do cool electronics type stuff without one. It seemed to me that learning to use a micro controller would be a good idea as well. I decided to follow the “Beginning Embedded Electronics Tutorials” at Anyway the tutorials were easy to follow and I ended up with this… 


 It worked pretty well, I have a basic 5V power suply running on my breadboard now and I managed to solder together a programmer for my AVR micro and could make things blink. Seems like a good first step