Keywords:
Electric wiring systems, Magnetic circuits, Symbols, Hearing aids, Signal-to-noise ratio, Electromagnetic compatibility, Circuits, Installation, Preamplifiers, Receivers, Buildings, Microphones, Electrical equipment, Design, Marking, Safety measures, Graphic symbols, Audio-frequency induction-loop systems, Electrical impedance, Aids for the disabled, Electronic equipment and components, Instructions for use, Electric cables, Communication cables, Purchasing, Amplifiers, Commissioning, Formulae (mathematics), Maintenance, Audiofrequencies, Design calculations