Electronic real estate lockbox system

Abstract

One or more lock or key units of a secure entry system is equipped with a radio receiver. The receiver permits a memory in the lock or key unit to be updated with new data that is modulated onto a radio frequency signal. By this technique, system-wide changes of programming data, such as changes of lockout lists and access codes, and changes targeted to specific units, such as disabling a particular key, can be implemented simply and quickly.

1 - 2 . (canceled)  
     
     
         3 . In an electronic key for use with an electronic lock, the key and lock being distinct from one another and movable relative thereto, the key including a microprocessor, a battery coupled to the microprocessor, a memory coupled to the microprocessor, a keypad including at least the digits 0-9, the keypad being coupled to the microprocessor, and a communications port for sending signals to the lock, an improvement comprising: 
 a receiver for receiving electromagnetic radio frequency signals; and    a decoder coupled to the receiver for providing data corresponding to a received radio frequency signal to the memory to change data stored therein;    wherein characteristics of the key can be programmed remotely; and    wherein the key is programmed to identify radio frequency signals carrying data intended for said key, as opposed to other signals intended for other keys.