Early Macalaster & Wiggin Tube

Ref. B13

This tube is 16” (40 cm) long with a five-inch (12.5 cm) bulb. It dates back to the first years of the 20th Century, with a platinum foil target backed by a relatively massive anti-cathode acting as a small heat sink. It illustrates the transition between light anti-cathode tubes and later tubes with heavy anti-cathodes supporting tungsten targets.

It has a concave-shaped aluminum cathode and anode electrodes.

The regeneration device contains some grayish fibrous material, probably asbestos.