You could turn on the paper tape punch at any time, and it would record every character sent to the printer. Then you could load the tape into the reader and turn it on and it would act as if you were typing at maximum speed (a whole 10 characters per second!) I don't recall any way to control either function remotely.
So, was switching from keyboard to tape input, or from printer to tape output, done locally at the teletype, or could that be controlled by the computer it was attached to ?
I guess this implies the paper tape format was basically just a dump/listing of sorts that might otherwise have been directed to the printer, and when used as an input this would then be read into a program (e.g. editor) that was really expecting keyboard (tty) input ?