On the Cover

Some “unborn” Kellogg AC tubes. As Alan Douglass describes them:

A Friend just presented me with a cigar box containing these four specimens, along with poop sheets for the McCullough and Kellogg tubes. Evidently someone toured the plant and fished souvenirs from the scrap barrel. These look earlier than any finished tubes I have. In particular, the getters are rings that slide down long wires welded to the plate. All the production tubes tubes I’ve seen , have either cup getters or little bent metal “roofs” to aim them away from the press. I can’t see how these unschielded getters would have worked (perhaps they did’n’t). Later tubes don’t have ribbed plates either.

My friend also pointed out that McCoullough was a 4-volt tube, while the Kellogg was 3. I nevere had noticed that, if I even had seen a spec sheet before (not sure).