Abstract: An antenna assembly (10) has a rotatable antenna arm (15) with an active portion (20) and a switching portion (25), a ground plane (30) and an inductive loop element (35) connected to the ground plane. In a first position of the arm (15), the arm is generally parallel to the ground plane (30) and the switching portion (25) is connected to the inductive loop element (35), forming a transmission line antenna. In a second position of the arm (15), the arm is extended away from the ground plane (30) and the switching portion (25) is disconnected from the inductive loop element (35), thus forming a whip antenna.

Abstract: A processor system comprising a control module (10) and a variety of subsidiary modules or boards (11, 12, 13) connected to the control module by way of a bus and an analog connector line. The control module comprises an analog-to-digital input (16) for receiving a signal on the analog connector line (25) and each of the subsidiary modules comprising an analog element (24, 28, 29) and switch (23, 32, 33) connected for selectively switching the analog element to provide an analog signal on the analog connector line in response to a control signal received from the control module, thereby to identify the presence and/or type of the option board(s) installed in the system.