Used to notify patrons that their table is ready, restaurant paging systems are run by a desktop transmitter. When the host or hostess pages a customer, he or she enters the code for the pager into the transmitter. The transmitter broadcasts an identification sequence--called the Channel Access Protocol, or CAP, code--specific to that pager. When the pager picks up the signal, it notifies the user by vibrating, flashing lights or playing a recorded announcement. Since frequencies vary by transmitter, the device's coverage area can range from a few hundred feet to several miles.
This antenna, made from a coil of wire wrapped around a metal core, listens for the transmitter to broadcast its CAP code. Once it receives the signal, the antenna sends it to the microprocessor.