check it out . I have the book somewhere and try to find it. It states it
was used by the Navy for transmitting military frequencies, not amateur.

I'll certainly try to do that. The reason for my doubt is that, in the 1950s, I
worked on Navy comm systems, in a factory and on some ships while working in
shipyards. Vessels ranged from tugs, landing craft, and minesweepers to a
cruiser.

Bill, K5BY