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.)
Expired
Application number
GB30329/25A
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.)
Societe des Etablissements Edouard Belin SA
Original Assignee
Societe des Etablissements Edouard Belin SA
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Filing date
Publication date
Application filed by Societe des Etablissements Edouard Belin SAfiledCriticalSociete des Etablissements Edouard Belin SA
Publication of GB244741ApublicationCriticalpatent/GB244741A/en
H03C1/46—Modulators with mechanically-driven or acoustically-driven parts
Landscapes
Transmitters
(AREA)
Abstract
244,741. Etablissements E. Belin. Dec. 16, 1924, [Convention date]. Copying-telegraphs; thermionic modulating systems; wired-wireless systems.-Electric oscillations generated by a valve oscillator are modulated in accordance with the non-vibratory move.- ments of the membrane of a variable-resistance microphone under the control of a device for exploring the reliefs of a document to be copied. In one arrangement, Fig. 1, the circuit of the microphone M and the plate circuit of an oscillating valve H are connected through transformers T<3>, T' respectively to a closed circuit connected through a transformer T<2> to line L. In another arrangement, Fig. 2, the current through the microphone M is amplified by a series of valves and applied to the valve H either in the filament-grid circuit as shown or directly to the grid. The valve H may be associated with a similar oscillating valve to transmit a beat frequency to line. The subject-matter of Specification 243,049 is disclaimed.
GB30329/25A1924-12-161925-12-01Means for producing a modulated electric current for systems of transmitting documents and the like
ExpiredGB244741A
(en)