Abstract: A cellular telephone system is upgraded by modifying subscriber units for selective service provider acquisition during roaming. Priority of acquisition is given to those service providers associated with the home service provider. These preferred service providers are identified by System Identification (SIDs) numbers. A roaming subscriber unit will tune to control frequencies to identify all of the system providers operating in a physical area to which the subscriber has roamed. The SIDs of those system providers available are compared to a preferred SID list contained within the subscriber unit. Selection is made based upon a priority of those system providers having arrangements with the home system provider. The SID lists in the subscriber units are modified based upon a version number for each update on the SID list.

Abstract: A cellular telephone system is upgraded by modifying subscriber units for selective service provider acquisition-during roaming. Priority of acquisition is given to those service providers associated with the home service provider. These preferred service providers are identified by System Identification (SIDs) numbers. A roaming subscriber unit will tune to a single broadcast frequency to identify available system providers operating in a physical area to which the subscriber has roamed.

Abstract: Automotive vehicle test equipment includes a controller which controls power supplied to a test circuit. The controller monitors a sleep mode switch which determines whether the controller enters a sleep mode. In sleep mode, the controller disconnects the test circuit from a power source. The controller also monitors a telephone line. Upon detection of a ring signal on the telephone line, the controller connects the test circuit to the power supply.

Abstract: An anti-tamper device in an automotive vehicle test system monitors an access panel to the automotive vehicle test system. An alarm is actuated if the access panel is opened. The automotive vehicle test system tests automotive vehicles and prints certificates which verify test results. The access panel is unlocked following the completion of an automotive vehicle test so that an operator can gain access to a printer to retrieve a printed certificate. The test system monitors the condition of the access panel even if power is removed from the automotive vehicle test system. A large capacitor provides power to monitoring circuitry. A data latch, powered by the capacitor, latches the condition of the access panel. The alarm is sounded when power is returned to the automotive vehicle test system and the condition of the latch indicates that an access panel has been opened.

Abstract: A wheel alignment system measures caster and steering axis inclination (SAI) by positioning the wheels at a right turn position and a left turn position. Toe, camber and inclination angle measurements are made for both wheels at both the left turn position and the right turn position. Based upon these measurements, caster and SAI are calculated either directly or through an iterative technique.