Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Compagnie des Telephones Thomson Houston
Original Assignee
Compagnie des Telephones Thomson Houston
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Compagnie des Telephones Thomson HoustonfiledCriticalCompagnie des Telephones Thomson Houston
Application grantedgrantedCritical
Publication of FR760420ApublicationCriticalpatent/FR760420A/fr
H04M1/00—Substation equipment, e.g. for use by subscribers
H04M1/26—Devices for calling a subscriber
H04M1/515—Devices for calling a subscriber by generating or selecting signals other than trains of pulses of similar shape, or signals other than currents of one or more different frequencies, e.g. generation of DC signals of alternating polarity, coded pulses or impedance dialling
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Engineering & Computer Science
(AREA)
Signal Processing
(AREA)
FR760420D1932-11-241932-11-24Perfectionnements aux dispositifs d'appel
ExpiredFR760420A
(fr)