Experimental Phototube, maker unknown
Tube photo-électrique expérimental, fabricant inconnu
Experimentelle Fotoröhre, Hersteller unbekannt
This tube was sold by FAIR RADIO SALES Co., Inc. (Lima, Ohio) under the reference XTUBE-98.
Some similar tubes from the same source have a slighly different design (xp002, xp003, xp037).
The end window has some semi-transparent coating; two radial pins connect to a heavily metallized deposited ring at the face.
The lateral tubulation port could have been used for the introduction of small evaporation sources to form the photosensitive layer.
A filament, partially coated, is inserted into a metal cylinder. Its resistance measures about 4 Ω.
Another collector has a similar tube with a paper sticker on it giving some sensitivity specs: "120 µA/L, 10/23/68".
One of the “long electrodes” has electrical connections at each end and is made of a folded thin sheet spotwelded into a tube-like structure. It would appear to carry a payload of material which could be resistively heated.
These tubes have defied the perspicacity of many vacuum tube specialists and collectors.
Hauteur • Height • Höhe : 10 cm • 4"
Diamètre • Diameter • Durchmesser : 52 mm • 2"
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The content of this site is under copyleft Der Inhalt dieser Website steht unter Copyleft
