Abstract: A method and system for affording security to a mobile phone (1) or other mobile device that involves checks by the device (1) on reception of a code transmitted repeatedly to it from a transmitter unit (8) of a transponder (7) that is interrogated by the device (1) and carried nearby the device-user. The absence of reception of the code by the device (1) resulting from theft or other loss separating it out of range from the transponder (7), together with detection of device-movement results in an alarm which if, not acted on causes, the device (91) to enter a lock-down mode in which it cannot be turned off without entry of a correct password or other person-identifier. In this mode, operation of the device is restricted to transponder-interrogation, GPS or other tracking, and server communication via the internet (3) enabling its location to be determined.

Abstract: Indicator apparatus for determining the miss distance of a projectile in relation to a fixed or moving target, comprising pressure-sensing transducers intended to sense the pressure wave generated by the projectile in at least four points, and means for generating corresponding electrical signals therefrom. The apparatus further comprises computer circuits, calculating the distance to the point of origin of the wave, i.e. the so-called "bang generation point", in response to the characteristics of the pressure wave. This distance has been called the "miss distance" in previously known indicator apparatus, but in accordance with the invention the miss distance is defined as the shortest distance between the projectile and target, and one object of the invention is to indicate this distance and the exact position of the projectile when it is at the miss distance from the target.

Abstract: The main features of the present invention reside in the fact that one or more remote groups of subordinated terminal units are serially interconnected and arranged in a closed loop which is terminated at the output and input of a master unit. Each of said groups and said master unit is connected to the transmission line via a modulator and a demodulator. In order to selectively connect a pulse equipment associated with each subordinated terminal unit, and adapted for transmission of data, with the transmission line, each of said subordinated terminal units includes a switching unit, which either connects or disconnects the associated pulse equipment from the transmission line.

Abstract: The main features of the present invention reside in the fact that one or more remote groups of subordinated terminal units are serially interconnected and arranged in a closed loop which is terminated at the output and input of a master unit. Each of said groups and said master unit is connected to the transmission line via a modulator and a demodulator. In order to selectively connect a pulse equipment associated with each subordinated terminal unit, and adapted for transmission of data, with the transmission line, each of said subordinated terminal units includes a switching unit, which either connects or disconnects the associated pulse equipment from the transmission line.