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.)
Publication date
Application grantedgrantedCritical
Publication of NL71860CpublicationCriticalpatent/NL71860C/xx
H04M9/00—Arrangements for interconnection not involving centralised switching
H04M9/001—Two-way communication systems between a limited number of parties
H—ELECTRICITY
H04—ELECTRIC COMMUNICATION TECHNIQUE
H04B—TRANSMISSION
H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
