227484 ⎘
Substation equipment, e.g. for use by subscribers; Circuit arrangements for preventing eavesdropping Lock-out or secrecy arrangements in party-line systems
Cellular device security apparatus and method
#2Cellular device security apparatus and method
#3Cellular device security apparatus and method
#4Changing a state of a remote switch box which connects a phone to a network
#5METHOD AND APPARATUS FOR CALL PROTECTION OVER A TELEPHONE SYSTEM
#6Cellular device security apparatus and method