[GreenKeys] WW2 IBM radioteletype network?

[Duncan Brown]

In the late 1930s, IBM produced the “Radiotype”, a IBM electric 
typewriter that could be used for radioteletype communications.  IBM 
supplied many units to the military during WWII.  IBM literature makes 
it sound like this was the only RTTY system in use during WWII, but of 
course, there were thousands of M15 in use, also.

The IBM system had a number of drawbacks.  It was too big and heavy for 
field use and used a six-level code incompatible with standard 
teletypewriter equipment. But the military apparently put up with it 
since the need for communications was so great during the war. IBM had 
leased the units to the government and took them back after the war.  
IBM sold the design to Globe Wireless in late 1945, partly to avoid 
being in competition with its good customer AT&T, but Globe apparently 
did nothing with it.  The units may have all been destroyed, since there 
have not been any reports of them showing up in surplus channels.





(note Morse keys - for backup?)


The "RadioType" could also interface with the SIGABA encryption 
machine.  See attached text for a description and how sensitive the 
machine was to vibrations & movement.

Have fun,

Duncan
K2OEQ




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p12


The IBM “Radiotype” equipment which worked with a SIGABA was not installed in the WDCC until several months after I was assigned there. In fact I was the officer at Arlington Hall given the task of familiarizing myself with it and then carrying it over and installing it in the WDCC.

This equipment plugged into the tandem outlet at the back of the SIGABA so that a punched tape of cryptograms was produced for carrying over to the Signal Center to work the transmitter or with incoming cryptograms plaintexts were typed directly on a sheet of paper by an Electromatic typewriter.

It seems to me now that it was a Saturday afternoon when I carried all the equipment from Arlington Hall to the WDCC. I hooked it up and plugged it in. But lo and behold it looked as if all the typebars on the typewriter were trying to type at the same time. I turned off the power and the bars returned to their resting position. But as soon as I flipped the switch on, all the bars were jammed together again. I couldn't figure out what was causing the trouble. Here was I, a first-lieutenant, who was supposed to be an expert on this apparatus and I was stumped. Finally I went over to the Signal Center and asked the master-sergeant in charge, the tall, somewhat slender but broad-shouldered and slightly stoop-shouldered, partially bald Sergeant Ferguson if he could help me. He explained the trouble readily and showed me how to cure it. Each key had a separate solenoid beneath it, to operate the key remotely from the SIGABA. Each solenoid had an iron rod that moved in a vertical tube. The sergeant explained that in moving the typewriter on the roads of Arlington most of these rods had moved enough by jarring to trip their corresponding typebar. So all we had to do was to hold all the operated typebars back, out of the way, and then release them one at a time to strike the paper. Each bar in operating restored itself to its proper resting position, and when all the operated bars had had their turn, the typewriter remained at rest, even with the power turned on, until the SIGABA sent it a signal. The solenoids were like the nerve endings from the brain in the retina. The solenoids could be operated electrically or by jarring; the nerve endings by light through the pupils or by pressure on the eyes.