File:HeTube.jpg

DescriptionHeTube.jpg Helium English: Image of a helium filled discharge tube shaped like the element’s atomic symbol. Deutsch: Leuchtendes Helium-Plasma:

favorite license. English Gas discharge tubes showing a spectral range of colors from the noble or inert gases - helium (He), neon (Ne), argon (Ar), krypton

use per a cada ús indicant-ne les pàgines on apareixerà. //ca.wikipedia.org/wiki/Fitxer:The_Groove_Tube.jpgFair useFair use of copyrighted materialtrue

De Forest transmitting tube which he called "Oscillion", VF = 37 V, VP = 1500 V 392 38 265 544 1476 1526 Spanish type B tube, VF = 6, VP = 20-150 667

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