How do radio stations know that you’re listening to them? Is there a signal sent back somehow?

Question

How do radio stations know that you’re listening to them? Is there a signal sent back somehow?

In: 2349

Answer 1

The main way they learn is by the sampling techniques mentioned by others. That is also part of the reason they have all those call-in contests. One way to show advertisers that people are listening is by seeing the boards light up as soon as they say “call in now.”