12AU7 = ECC82. serving as a desirable ECC82 = 12AU7 tube; representing the best of its kind. AUTHENTIC 1955 Amplitrex AT1000 TESTED RCA 12AU7 MATCHED PAIR TUBES. REAL 1955 N.O.S. RCA USA 12AU7. REAL NOS 1955 RCA BLACK-PLATE 12AU7 PAIR.
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NOS is subject to interpretation and there is no specific definition for it either. There are suggestions and opinions. special checking. This test needs sound amplification; hearing listening to noise with headphones would indicate a real disaster inside a tube (THE shorts test WOULD already BE evidence OF THIS).
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Tubes that test within certain specifications may be considered good or usable, but whether they are specifically labeled NOS DEPENDS on the history. special checking. This test needs sound amplification; hearing listening to noise with headphones would indicate a real disaster inside a tube (THE shorts test WOULD already BE evidence OF THIS).
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One slyvania 12ax7 tube made in US Gray plate, round getter Tested with a TV-7 tube tester with a min good value of 32/32 Tested: 64/66
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ECC83 12AX7 Valve Tube. Long Black Plates, Square Getter. RCA, Made in USA. Fully Tested on AVO VCM 163.
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NOS tubes fall within the Gm characteristic range of an average tube, as published in the RCA RECEIVING TUBE MANUAL, which states "Individual tubes, like any manufactured product, may have characteristics that range above or below the values given.
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1950's Amperex Bugle Boy 12AU7 ECC82 Audio Tube. 1940, 40s, 1950, 50s, 1960, 60s, 1970, 70s. Tube(s) shown in pictures will be the exact tube(s) you will receive.
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