The principle of operation of the personnel call button R-300B BELLS
When the button is pressed, a bright LED light up – red or blue. The signal immediately goes to the pager-watch of the medical personnel and to the call receiver. The screen of these devices displays the number of the ward (in the hospital) or the calling table (in the restaurant). A nurse or waiter sees where the call came from and immediately rushes to the place of the call.
Call signal up to 100 meters indoors and up to 300 meters outdoors. And if you install an additional repeater, the range will increase, respectively, up to 300 meters and 700 meters.