An athlete training device includes a first sensor pad for signaling when a first object has been removed from the first pad and a second sensor pad for signaling when an athlete’s hand has been removed from the second pad. A method includes detecting and reading a tray label of a tray being placed on or in the mail processing machine to determine a tray identifier. The system works to discriminate among failures in operation of the output shaft angular position sensor and the encoder and another type of a failure using outputs of the sensors. Then telecommunication service provider will send a confirmation briefing to a display interface of the user’s bidirectional wireless communication equipment after receives the user’s transmission number. In addition, the present invention also relates to a process for the preparation of the salt according to the invention, to the use of the salt in an electronic device, and to a formulation and an electronic device which comprises the salt.