(under subclass 2) Systems in which vibrating means, reeds, tuning forks, diaphragms, or rotary circuit interrupters, etc., are utilized in transmitting or receiving undulating currents and fundamentally characterized by the production of musical tones easily distinguishable from one another, so that a plurality of messages may be simultaneously transmitted over the same line.
SEE OR SEARCH THIS CLASS, SUBCLASS:
51, for simultaneous transmission of currents of different frequency, with tuned or resonant circuits, and usually generated by alternating current machines or equivalent.
82, for so-called "auto-dot" transmitters for transmitting
dots by vibrating or reed circuit closers or interrupters.
SEE OR SEARCH CLASS
84, Music, 723+, for electric music instruments provided with a tuned sound wave generator, which may be used to produce electric currents or potentials of a particular wave form.
200, Electricity: Circuit Makers and Breakers,
19.01+, for periodically actuated switches.
333, Wave Transmission Lines and Networks,
186+, for wave filters of the electromechanical transducer type.
335, Electricity: Magnetically Operated Switches, Magnets, and Electromagnets,
78+, for electromagnetically operated periodic switches.
336, Inductor Devices, appropriate subclasses for transformer and inductive reactor structure, and especially
130+, and the subclasses specified in the Notes thereto, for inductor devices which have a movable core (e.g., vibrating reed, etc.).
340, Communications: Electrical,
825.38+, for party line selective systems, not restricted to telegraphy, utilizing needs.
379, Telephonic Communications, 180, for application of reeds to call systems in telephony.
