Rare Mullard Amperex 12AX7 ECC83 Tube Black Label mC2 Tube D-Getter 12ax7a B339

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Here we have for sale is a very rare Mullard Amperex 12AX7 / ECC83 Black label tube. Produced by Amperex and labeled for distribution by Mullard. Circa 1958 mC2 tube with the 17mm long grey plates and foil strip D-getter. One of the best early production 12AX7 ECC83 tubes you can buy! Great used tube testing strong with lots of life remaining. Mullard label is worn as shown. Clean straight corrosion free pins. Tube has had 2x full parameter testing for Gm, La, Shorts and Gas with included Amplitrex results shown in photo. Tube tested with a quality/matching grade of 8 on the Divo tester showing again the tube strength and nice balance across the triodes. Tubes codes shown in photo and are mC2/<8J. Great tube here! Don’t miss this one!! Tube will ship professionally packed in a new Mullard box as shown. Please ask any questions prior to purchase. PLEASE READ the description page and sale terms fully below. Thanks for looking!!

Tubes undergo dual testing procedures whenever possible. We utilize fully calibrated and modernized Hickok 539c, AVO 163 or Triplett 3444-A and Amplitrex testers. Then digitally tested and displayed on the Divo/Orange tester for its ease of interpretation by buyers. As a result, you are assured to be getting some of the finest quality, fully tested and proven vintage tubes available for sale. Tubes have undergone and passed all the following testing.

Heater filament test: Short circuit

Heater filament test: Open circuit

Heater filament test: Tolerance check

Heater cathode insulation: Leakage

Heater cathode insulation: Short Circuit

Tests for heater current abnormalities

Amplification factor

Voltage gain

Power gain

Screen grid test

Mutual conductance test

Dual test for double triodes

Emission

Inter electrode leakage

Inter electrode short circuit

Flash-over (arc detection, high voltage breakdown)

Gas ionisation test

*** SALE TERMS - PLEASE READ COMPLETELY ***

We ship direct to addresses inside the USA ONLY. Any international sales & shipments are handled strictly via the Global Shipping program with no exceptions when a listing has that shipping option made available. Due to the fragile and sensitive nature of vintage tubes and electronics we DO NOT ACCEPT RETURNS due to the myriad of factors including but not limited to the buyers unknown equipment condition, bias settings, misuse or mishandling etc. We will certainly work with any buyer to address an issue such as a rare occurance where an item arrives damaged in shipping. We require any buyer that encounters a problem to notify us within 72 HOURS after delivery of a pending issue. As a potential perspective buyer, please be aware that if you feel you can not adhere to and honor the sales terms of our listings, we kindly and respectfully ask that you DO NOT PURCHASE tubes from us. Unless specifically stated in the listing and commonplace amongst the majority of tube sellers, we do not warranty or make any guarantees related to noise, hum, microphonics or tube performance in any unknown equipment. As is commonly understood, tube testing results do not necessarily translate between different brands and models of tube testers and the different approach each manufacturer used to achieve their test results. As a result all tubes listed for sale are represented and sold on a AS-IS basis and STRICTLY off the results shown and provided by the test equipment used in the listings. As a buyer, you are purchasing based solely from the test data provided and your comfort in our feedback ratings. No added terms or expectations not specifically assured in the listing description will be entertained post transaction. Please ask questions or concerns prior to any purchase! All the testers used are some of the most respected models ever produced and are professionally calibrated regularly. Calibrations are checked routinely using “bogie standard” tube sets dedicated for each tester. All the aforementioned factors ensure solid and accurate results for the tubes tested and confidence for the buyer in the vintage tubes being purchased. Therefore please let it be understood that we will not guarantee or compare the results off any other tube testers. Partial refunds or returns will NOT be granted based off claims made from unknown testers and their obviously unknown condition and accuracy. As a courtesy, every tube we sell is cleaned and treated with Deoxit to remove 50+ years of corrosion and grime. We recommend that users clean or Deoxit their tube sockets occasionally for best tube performance.