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 of NL228720ApublicationCriticalpatent/NL228720A/xx
H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
H04L15/00—Apparatus or local circuits for transmitting or receiving dot-and-dash codes, e.g. Morse code
H04L15/24—Apparatus or circuits at the receiving end
H04L15/26—Apparatus or circuits at the receiving end operating only on reception of predetermined code signals, e.g. distress signals, party-line call signals