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Summary
DescriptionVacuum tubes octal, miniature.agr.jpg
English: A full size and a miniature vacuum tube for size comparison. The larger tube, an octal-base 5U4GB dual power diode, was made by General Electric in the United States, the smaller, an ECC-83/12AX7 dual triode, was made by Telefunken in West Germany. The smaller tube is 1-3/4 inch (44.5 mm) high, not including pins, and 0.8 inch (20.4 mm) in diameter; the larger tube is 3-5/8 inches (93 mm) high, not including pins, with a base (black portion) 1-3/8 inches (35 mm) in diameter.
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