Week 6

We have reached a standstill because we are not getting the circuit modulate the signal correctly.  Meaning that when we hook up the circuit to the oscilloscope and swipe our card, we are not getting a useful signal to determine differences between cards.

This signal is what shows up on the oscilloscope after we put a RFID card on there, this signal is supposed to look like a sine wave with a quick frequency change that would represent 1's or 0's.  This wave does not change for any RFID tag.  Currently we are working with fellow students and teaching assistants to figure out the problem, but are having little success. 

Week 5

Since last week, we were receiving help from an Electrical Engineer at our school.  Through his help we were able to build a smaller, more convenient circuit board.  However, when testing the board we were unable to generate any kind of nice looking signal, the reason being is unknown so we had to roll back to using a breadboard design.

Through this design we were able to generate the correct carrier wave, but wasn't being modulated correctly by the cards.

Week 4

From last week we were unable to produce any kind of wave.  However we noticed that there were some connection issues in the board, so for the mean time we were able to fix the board and produce a square wave with a period of 8ms for reading 125 kHz.  After this we need to make a more permanent board and edit some program stuff.

Week 3

In Week 3, we created a circuit board for the RFID reader as shown in the picture.  From this we attempted to create a square wave with a period of 8ms because that frequency would read at 125 kHz.  Unfortunately it didn't work so, we had to go back and check some things in the board and the program.