The Hughes Memo-Scope 104-D is a very early storage CRT scope.
The units are quire rare, almost as rare as the manuals. I like my 104-D very much! It is easy to use and still holds the image well after so many decades. The manual and included suppliment is high resolution 300DPI and about 65MB. Free as usual.
I got the manual from WJ Ford Enterprises years ago. They are sadly gone. There is no harm in posting the manual now. I hope there are more 104-D's around somewhere.
http://www.bunkerofdoom.com/lit/hughes104d/hughes_104d_pub.pdf 
