Reference tube is tested first then the tube listed for sale. Test procedure.
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SYLVANIA JAN CHS 6SL7GT VT-229 Valve Tube Black rolled plates Dimple foil getter Code SC966A Date code D 4 April 1954 Hickok test = 2000/1950 used
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2 PCS 6N9S ( 1579 6SL7 ). • Input capacitance of the first triode 3 pF. • Input capacitance of the second triode 3.4 pF. • Output capacitance of the first triode 3.8 pF. • Output capacitance of the second triode 3.2 pF.
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Hickok test 1600/1600 umhos GM
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6SL7GT Grey Plate Ring Getter Brown Base NOS Brimar UK Valve Tubes.
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6SL7GT Black Palte D Getter With 3 Crown Hallmark NOS RCA USA Valve Tubes (VT23).
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NOS RCA 6C8G(6SL7 FAMILY) BLACK PLATES/HICKOCK TESTED
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SYLVANIA JAN CHS 6SL7GT VT-229 Valve Tube Used Tested Strong Black rolled plates Dimple foil getter Hickok test = 1800/1850 mhos gm new test
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