Those numbers are projected based on surveys and I would imagine some radios reporting back like cable boxes. A traditional radio gives no indication that it is listening to any particular band.
I've wondered how they'd track that. Is there a clever way to send a signal back to the source? I imagine there's no easy way to measure the outgoing wave in a noninvasive way
For a modern radio in a car there are so many possible ways to send info back. None of them are clever just extra electronics that you are unaware of inside the car, basically a bug.
If you were to build a simple radio receiver there is no way to find that.
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drakesdoom ago
They already have encrypted channels for important stuff. They don't care if you listen in on general dispatch anymore.
Anson ago
was it ever used as I'm saying?
and if so, are they still doing that?
drakesdoom ago
Not really, listening to a ready is passive. Unless you said something you could listen all you want and they would never know.
Anson ago
they know how many people are listening to a radio station at once, why wouldn't they know about the police scanner?
drakesdoom ago
Those numbers are projected based on surveys and I would imagine some radios reporting back like cable boxes. A traditional radio gives no indication that it is listening to any particular band.
Anson ago
I've wondered how they'd track that. Is there a clever way to send a signal back to the source? I imagine there's no easy way to measure the outgoing wave in a noninvasive way
drakesdoom ago
For a modern radio in a car there are so many possible ways to send info back. None of them are clever just extra electronics that you are unaware of inside the car, basically a bug.
If you were to build a simple radio receiver there is no way to find that.