Tester 12AT7 Expected Gain (Mu) value = 50. Transconductance (Gm) Section B = 1904. Transconductance (Gm) Section A = 1961. TESTED ON A MAXI PREAMP II TUBE TESTER FOR GAIN(Mu), TRANSCONDUCTANCE(Gm) AND NOISE(dB).
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Tubes tested above expected dataset for a new tube using our eTracer on a full curve map. The 6679 is a communications grade 12AT7, very high quality. Triode #1 - Plate Current = 6.96mA \ Rp = 14816 \ Gm = 4891 \ Mu = 72.5 \ Corners = PASS.
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These were made for industrial use, and can take long periods in full cutoff without changes in characteristics. Large Black Ladder Plates, D Getter.
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Hi tested good. Min value 50/50.
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Model: 12AT7WB ECC81 ECC801S. Rare solid disc version, green printing, tested NOS, balanced sections.
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For sale is a RARE Matched Pair GE JG-6201/12at7/ECC81 Black Plates Triple Mica tubes D-getter. Made in USA. All tubes are also tested for noise and microphonics. Tests very strong at NEW level and tightly matched.
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Matched pair testing very strong.
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This is a made in USA version and has a faint Amperex orange globe. Tests at new specs.
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