AN/GRA71 Burst morse sender

The AN/GRA71 is a magnetic tape based high speed morse keyer which sends a morse code message previously recorded on a magnetic tape cassette using a manually operated recorder with dot, space and dash keys.

The keyer operates at a relatively high speed of 300 words per minute and (as far as I can tell) the dot and dash periods are equal length (certainly the tape advance seems to be the same).

My dad found this setup when looking at some optical equipment he wanted and bought it for me, but I never came by suitable receiving equipment or a compatible radio.