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Publication of BE575422ApublicationCriticalpatent/BE575422A/fr
H04M19/00—Current supply arrangements for telephone systems
H04M19/08—Current supply arrangements for telephone systems with current supply sources at the substations
H—ELECTRICITY
H04—ELECTRIC COMMUNICATION TECHNIQUE
H04M—TELEPHONIC COMMUNICATION
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
H04M1/31—Devices which can set up and transmit only one digit at a time by interrupting current to generate trains of pulses; by periodically opening and closing contacts to generate trains of pulses
H04M1/38—Pulses transmitted by a movement variably limited by the setting of a stop