The writer of the goof was evidently unfamiliar with the difference between American Morse and International Morse. Several characters are different including the letter O. In the 19th century the railroads and Western Union used American Morse for DC telegraphy which was supplanted by International Morse that is used in radio telegraphy. So two dots was correct. After watching all the episodes I was impressed with how they handled the telegraph apparatus, even if the code was gibberish. The operators always opened their shunt key before sending and closed it after sending.
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