2010-12-13

radio experiment #2

Having received a radio signal I wanted to build a transmitter and receive my first radio transmission. I found all necessary instructions at scitoys.com, which is an amazing repository of various interesting experiments that anyone can do using ordinary household rubbish.
Thus, I took on a challenge to build an AM transmitter.

On the contrary to the AM receiver from the radio experiment #1, I needed to use an additional source of power to run the transmitter. I also used some more advanced manufactured components, such as a crystal 3.6864 oscillator and a sound transformer. Last but not least, I needed content for my transmission, distinct enough to be recognised in the overwhelming aether noise and among many faded radio stations.

This is how my AM transmitter looks like.



With an amplified AM receiver and using separate wire antennas, and separate grounds I succeeded in receiving a faded signal. The further from the source of the transmission I moved, the fainter it got, but anyway—I sent it through the wireless, even though it all happened in one room.

Maybe using more power would increase the reception? Maybe the primitive wire antenna was impeding the transmission? Maybe I needed a different oscillator or a better receiver? All this might be solved in next experiments.