There's two-way pagers which transmit, but receive only pagers can be broadcast reception only; there's no check-in / message acknowledgement, although messages may be rebroadcast to help ensure reception in case of bad signal conditions.
You'd probably get some small amount of RF emissions though, most receivers radiate something as a result of using superheterodyne signal processing.
There's two-way pagers which transmit, but receive only pagers can be broadcast reception only; there's no check-in / message acknowledgement, although messages may be rebroadcast to help ensure reception in case of bad signal conditions.
You'd probably get some small amount of RF emissions though, most receivers radiate something as a result of using superheterodyne signal processing.