Philips Valve Tube - Model 28001/00 (ca. 1940s)
This valve (rectifying) tube was made in Holland by Philips, probably in the 1940s. Complete with cooling fins, dark glass and chrome metal—this is as cool as a valve tube can get!
The identification plate indicates that the "Type" number is 28001/00 and the maximum kVp is 125 volts. It indicates three current—voltage combinations for the filament: 200 mA, 13.5 V; 400 mA, 14.6 V; 1000 mA, 16.5 V. What might be a patent number is also indicated: 24 163 263.
Generously donated by Ron Kathren.