It's how the TV detectors work in countries, such as the UK, that charge a license fee for TVs.
Military radios can't use this common technique because of the risk of detection.
I suspect pagers only receive on 1 or at most a few frequencies. If that's correct, they wouldn't need that technique.
It's how the TV detectors work in countries, such as the UK, that charge a license fee for TVs.
Military radios can't use this common technique because of the risk of detection.
I suspect pagers only receive on 1 or at most a few frequencies. If that's correct, they wouldn't need that technique.