By K4KJ - great reading!
Shortwave Receivers, National NC-60 and NC-98 pictures and information.
Pictures of both the NCX-3 and NCX-5 Transceivers.
Pictures and technical information.
A 1946 radio - with picture and technical details.
A rather low resolution picture.
Some basic information from "Ominous-valve"
National SW-3 "Thrill Box" receiver from the 1930s, with photos.