The receiver worn by a sight or heating-handicapped person receives signals from a transmitter which is activated by a door bell, telephone, or similar. A physical signal is provided by a pointed electrode on the receiver casing which is located against the skin of the wearer. The electrode, which is lightly spring-loaded, acts as one pole, with the wrist strap of the receiver, suitably made of metal, acting as the other. It has reduced contact with the skin of the wearer so as to ensure a reduction in current level. - Nevertheless, it is necessary that the wrist strap has a large contact surface with the skin since the latter often is dry, and thereby a poor conductor.
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