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Application filed by Standard Telephon & Radio AgfiledCriticalStandard Telephon & Radio Ag
Publication of CH323473ApublicationCriticalpatent/CH323473A/de
H04M1/00—Substation equipment, e.g. for use by subscribers
H04M1/26—Devices for calling a subscriber
H04M1/30—Devices which can set up and transmit only one digit at a time
H04M1/50—Devices which can set up and transmit only one digit at a time by generating or selecting currents of predetermined frequencies or combinations of frequencies
H—ELECTRICITY
H04—ELECTRIC COMMUNICATION TECHNIQUE
H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS
H04R21/00—Variable-resistance transducers
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Engineering & Computer Science
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Signal Processing
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Physics & Mathematics
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Acoustics & Sound
(AREA)
Telephone Set Structure
(AREA)
CH323473D1954-08-241954-08-24Vorrichtung mit schwingenden Zungen
CH323473A
(de)
Regelungsvorrichtung an elektrischen Hupen, deren Membran auf einem vertieften Gehaeuseteil befestigt ist, der in einer mittleren OEffnung den Magneten enthaelt, durch den ein den Anker und die Membran verbindender Bolzen hindurchgefuehrt ist