Note
QST, Oct 1971, p. 140.
QST, Jan 1972, p. 151.
Appears to be the first programmable electronic keyer.
The Curtis EK-402 keyer had four quadrants of 64-bit programmable memory. They were selectable in three banks (quadrants three and four were linked together). The programmable messages had a delay and repeat function. The EK-402 had an internal AC supply. A 9 volt battery retained programmed messages when the key was disconnected from the AC line.