Note
QST, Jul 1955, inside back cover. "Coming soon!"
QST, Oct 1955, p. 160. "Available now" / specs.
QST, Nov 1955, inside back cover. (lots of detail)
QST, Feb 1960, p. 141.
References
Technical description. Radio News, Oct 1955, p. 96.
Adding WWV. CQ, Feb 1959, p. 39.
Revisions. CQ, May 1959, p. 41.