AMPLITREX TESTED Perfectly Balanced NIB / NOS Amperex made / Zalytron labeled ECC83 / 12AX7 Twin Triode tube.  Made in Holland, July 1960.  Features long, ribbed plates with a top, solid Halo getter.  Tests VERY STRONG at 1,900 (119%) / 1,900 (119%).  NEW spec average for this type is 1,600 (100%) / 1,600 (100%).

    All tested tubes are analyzed on a new Amplitrex AT1000 digital tester.  The AT1000 is the most accurate and reliable tester ever made.  All tubes are tested for heater-to-cathode leakage / shorts, emissions, transconductance, and a gas test.  In most cases, I will provide a computer generated spreadsheet of the comprehensive results for your records.  In either case, emission and / or transconductance measurement will be posted on every tube box for your convenience.  

    Results will be given with the actual number measured and then a generated percentage.  This percentage is based on specification values of a NEW tube so you know how good a tube is.  Ideally, a "new" tube should read at 100% or greater, but some NIB / NOS tubes will test in the middle to upper 90 percentile.  Tubes that test "NEW / NOS"  may not necessarily be true NOS.  New in the box tubes will be listed as NIB.  Two or more tubes are considered "matched" as long as they test within 10% of each other for emission (mA) or transconductance (mhos).