Digital transmission and reception

Thread Starter


Joined Dec 20, 2011
I just spent an entire hour typing something. I wanted to undo a line that I typed so, naturally, I click the undo button; it deleted everything!! :( Now I have to start over and get my project thought out. Here I go:

The project is kind of like a touch screen drawing application.
The difference is that instead of a touch screen and beautiful colors, you have push buttons and one color LEDs.

I want to push a button on a hand held pad and wirelessly turn on the corresponding light on a display pad across the room.
Basic Plan:
1.) You push a button in an array of buttons
2.) The row and column of the button is decoded
3.) The button address is modulated onto an FM (or AM) signal
4.) The FM (or AM) signal is received by the receiver
5.) The row and column address is decoded
6.) The corresponding J-K flip flop is triggered, thus turning on the LED

This is actually a miniature version of what I want to do. However, if I get this working, I will have the knowledge needed to get the bigger version done quickly. If you're not curious of the 'bigger project' skip the next paragraph.

What I want to add to the project is a way to save or edit a 'frame' and animate through the list of frames. This would require RAM of some sort, counters, and registers. I want to master the FM or AM modulation and sending of binary data before I start dealing with the seemingly more complicated binary stuff.

What I know: I can get the button row and column encoded.
What I don't know: I don't know how to transmit or receive the binary data using an FM signal.

I know how to get sinusoidal information onto and off the carrier but, I don't know how to get digital data onto or off the carrier. I have heard of frequency shift keying and phase modulation but have yet to mess with the circuits involved. Transmitting and receiving digital data is what we are currently covering at ITT Tech. Since, we're out for Christmas break, I can't use the equipment or complete the step-by-step 'looking at the waveform' labs. I have looked over them and they are of no help.

Does anyone have a tutorial or lab for digital transmission and reception? <-- currently googling