General Electric D-1.7 X-ray Tube (ca. 1940s-1950s)

A fairly small General Electric diagnostic X-ray tube. As you might guess, the "D" in the tube designation (D1.7) stands for diagnostic. The "1.7" indicates that it was a relatively fine focus tube. More specifically, this number indicates the approximate diameter of the projected focal spot in mm.

Quoting the 1953-1954 GE catalog: "This is a special Coolidge tube, with an exceptionally fine focal spot, developed for use with the D-3 and D-4 Mobile X-Ray Units. In combination with adequate focal-film distances, it makes possible the production of radiographic detail that could othetrwise be obtained only at greater distances and with higher energies."

Size: Approximately 6" long, 2" diameter

Price: $155 in 1953-1954 GE catalog

This particular tube belonged to M. J. Gross who worked with Dr. Coolidge at General Electric in Schenectady N.Y.  Gross later became Vice President of the GE X-ray Company. During the 1930s and 1940s, Gross and Zed Attlee formed the core of Coolidge's research and design team.

Kindly donated by Malvern Gross Jr. in memory of his father.

References

• General Electric Catalog. X-ray Supplies and Accessories. 1951.
• General Electric Catalog. X-ray Supplies and Accessories. 1953-1954.