Abstract: A method and apparatus is disclosed for simultaneously indicating on each of a plurality of communication terminals, instructions transmitted by each terminal and the identity of the respective terminals that transmitted the instructions. Such a feature can be used to indicate the moves of parties playing a game over a telephone line. Once a communications link is established between two or more parties, their terminals are placed in a game mode which activates inband signal detection and player identification circuitry located within the terminals. Multi-colored indicators and player identification displays at each terminal are activated, their color being dependent upon the source of received instructions. In one embodiment, player identification indicators may be incorporated into a touch tone keypad located on the terminals. The keypad's touch tone keys are modified such that each key has two or more color coded indicators incorporated within, each color representing a particular player's move.

Abstract: A strain sensing apparatus includes a pair of magnetic layers disposed on a shaft to which an external force is applied to cause strain in it. The magnetic layers have magnetic permeabilities which change in opposite directions in response to the strain in the shaft. A sensing coil is disposed to face the magnetic layers with a spacing disposed between the coil and the magnetic layers. An exciting AC voltage is applied across the sensing coil. A change in self-inductance of the coil caused by the permeability changes of the magnetic layers due to the shaft strain is derived as an electrical signal representative of the magnitude of the shaft strain.