Just wondering if anybody here knows anything about high speed Morse. Seems like it was used in the 1940s, maybe earlier and later, sending Morse at speeds of 500 wpm or so. Transmission was from punched paper tape, and reception was on ink recorders; then operators transcribed the received messages to hard copy. The ARRL handbooks in the '40s and '50s had ads in the back for T. R. McElroy Co., and their line of keyers and ink recorders and other accessories.
I'd like to know more about who used the technology, when and where it was used, modulation method, how much power, and what caused it to go into non-use. There is a little bit about it in the online book "The Art and Skill of Radio Telegraphy" where it was said to be used between the Army HQ station WAR and the various Army headquarters in 1940 or so.
