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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Matched pair of NOS Hammond screened musical audio tubes. Tubes that test within certain specifications may be considered good or usable, but whether they are specifically labeled NOS DEPENDS on the history.
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You are bidding for one pair Siemens 5751 E83CC ECC83 12AX7 Triple Mica NOS Matched, Pair Price Made In Germany Nos without boxes. There are many in stock. Besides, I have a big collection of a variety of tube types which are almost near mint and so rare. These are tested carefully on my TV-7D/U and AVO CT160 tube testers at the nos range and on my amplifier. They all work fine. The items will be shipped from Hanoi, Vietnam by SG link through Ebay Cpas with track at 18.65 pounds. It may take from 22-45 days. If you need the tubes urgently, please pay an extra to use express services like DHL, FedEx... Please let me know soon. Thanks
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The tubes are super rare, hard to find and in mint condition. The tubes are carefully tested on my tube tester TV-7 at 49-50 and 48-49/32 min good.
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The sonic top echelon! authentic munich (munchen germany) etch codes visible. + leak / short / gas check. (important longetivity indicator). life test pass! our high power gm output test applies up to 250v w/ filtered dc, more than many other testers.
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Special Ruggedized. 'MZ"6681 12AX7WA' with original. -Glass Etched '12AX7WA' with GE Domino Dots. For Reference (from the GE Engineering Data Sheet for 6681/12AX7WA / E83CC ube dated shown in pics).
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The tubes are near mint unused only tested on tube testers and on amplifier as shown in the photos. Testing results are clearly shown in the photos. There are several pairs available. What you see is what you get.
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1960s PRODUCTION. 1 X CV4004/E83CC TUBE. TESTED IN ROEHRENTEST TUBE TESTER 87/80% EMISSION (EM).
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