When illuminated by a radio beam from a remote location, the cavity would return a frequency modulated signal.

A high frequency source with a high rotation rate should do it, perhaps a frequency modulated one.

They also make shorter pulsed, frequency modulated calls.

For example, this could be done with a single-sideband modulated or frequency modulated signal.

A stochastic (or frequency modulated) dot pattern creates a sharper image.

The C track also contained audio channels three and four, frequency modulated.

Another voice cut in: "More frequency modulated stuff, sir.

The message was a simple one, frequency modulated around one and a half megahertz, repeated for a few minutes every day of Galactic time.

His company was one of the first to produce frequency modulated radios, cutting out static interference for clearer reception.

These wolf-whistle cries are known as frequency modulated (FM).