The circuit to create waveform like this is based upon a simple relay that is driven by a clock signal.

The circuit was designed to be able to obtain signals via amplitude modulation where the sensitivity and selectivity is fairly good. Amplitude Modulation AM – a method of emphasizing data on an ...

In modern communication systems, modulation is a key function that embeds the baseband signal (information) into a carrier wave so that it can be successfully broadcasted through a medium such as air ...