[GreenKeys] on-off radio teletype (not FSK)

[Nick England]

How common was on-off radio teletype (not FSK) back in the day?
Did hams ever use it or was it strictly a military or commercial thing?

This question poked up in my mind as I was scanning the manual for a 1952
RTTY converter designed for 60-600 wpm on-off keying.
http://www.navy-radio.com/manuals/r466-uc-man-91612-5202.pdf
One block diagram shows it being used to receive on-off tone signals via
VHF that were generated originally from an AN/FGC-5 which is a gadget that
time-multiplexes four TTY lines together.

Nick England K4NYW
www.navy-radio.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/greenkeys/attachments/20180216/5950e11d/attachment.html>