This is the project found in a 1981 publication, but it is still viable. It is a simple AM transmitter, a device in which you speak, and your voice comes out on any AM radio placed in your vicinity. The range of this device, of course, is small, on the order of a few meters, but it is an excellent experimental setup that may even have its performance improved. Basically, the oscillator operates at a much lower frequency than that determined by the average wave range (550 to 1600 kHz) but as there are many harmonics in its oscillation, by adjusting P1 it is possible to cause signals to be irradiated. The transformer used in this assembly is output for transistors with primary impedance of the order of 1k and the speaker used in its secondary serves as a microphone.
