General Electric XPD Tube (ca. 1930s, 1940s)

This General Electric XPD Coolidge tube is a single focus dental X-ray tube that was probably manufactured in the 1930s or 1940s.

The letters "XP" refer to "X-ray Protected." The "D" either stands for "dental" or "diagnostic." Not sure which.

There is small mushroom-shaped aluminum device at the end of the support arm for the anode. It is undoubtedly there for heat dissipation, but it would seem to be a somewhat inefficient design for this purpose. Unless, there was minimal heat generation to begin with.

Size: ca. 12" long, 2" diameter

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

Reference

General Electric X-ray Corporation. Coolidge X-ray Tubes - Kenotrons. Bulletin No. 293. 1934.