Abstract: A third generation (3G) mobile communication system supports an over-the-air activation scheme utilizing a wireless packet data protocol. A subscriber identity module (SIM) is preloaded with temporary operating parameters such as a temporary international mobile subscriber identity (IMSI) that is used for initial access to a network. Once a packet data protocol communication link is established between the mobile device and a network support node, the user may remotely subscribe to a number of service terms using the mobile device. In addition, an activation procedure is carried out to assign permanent operating parameters, e.g., a permanent IMSI, to the SIM. After activation, the user can remotely modify existing terms or remotely enroll in additional service features via a wireless IP link between the mobile device and a network support node.

Abstract: An apparatus for measuring phase angle difference between two conductors uses a hot stick, a field unit, and reference unit. Voltage is sensed at a conductor, and the voltage is passed through an automatic gain control which adjusts the voltage input to a voltage detector to a level which prevents saturation of the voltage detector. Non-saturation of the voltage detector enables detection of all of the data in a detected sine wave. Pulse width modulation and pulse width modulation RF transmission are used to provide for data transmission from a hot stick to a field unit.

Abstract: A variable potentiometer with a wiper terminal and first and second terminals has relay switches for shorting or for unshorting resistors. When resistance is reduced between the wiper and one of said terminals, resistance is increased between the wiper and another terminal. In one embodiment two strings of resistors with the same nominal values are used between the wiper and the terminals. In another embodiment, a single string of resistors are used and are switched into either the electrical connection between the wiper and the first terminal or between the wiper and the second terminal. When resistance is lowered between the wiper and one of said first or second terminals a first resistor is replaced with a first short circuit and when resistance is increased between said wiper and another of said first and second terminals a second short circuit is replaced with the first resistor.

Abstract: A variable potentiometer with a wiper terminal and first and second terminals has relay switches for shorting or for unshorting resistors. When resistance is reduced between the wiper and one of said terminals, resistance is increased between the wiper and another terminal. In one embodiment two strings of resistors with the same nominal values are used between the wiper and the terminals. In another embodiment, a single string of resistors are used and are switched into either the electrical connection between the wiper and the first terminal or between the wiper and the second terminal. When resistance is lowered between the wiper and one of said first or second terminals a first resistor is replaced with a first short circuit and when resistance is increased between said wiper and another of said first and second terminals a second short circuit is replaced with the first resistor.