... .How it works?When the patient need service, he can press the call button, the bed number signal will be sent to the ... result by softer ware.5,Work mode: one-to-one, more-to-one, one-to-more6,Signal Coverage:5000ft (in open area)7,Compatible ... with one to five key pager specificationFrequency 315MHzModulation ASK(AM ...