This listing is for one (1) Type 81 UX-281 RX281 Half-wave rectifier antique vacuum tube in the globe (S) tube shape. It has a 4-pin base, black plate, and bottom foil or square getter. Labels in stock include RCA, Radio King. If you're looking for a particular brand, please message right as you order - we pack and ship quickly!

Inv code 6U8

Your tube has been fully tested on a computer-regulated, USA-made Amplitrex AT1000 on Fixed Bias setting with like new, NOS results (tNOS). Here's what that means: to qualify for this listing, several stringent conditions must be met: The transconductance for each section must measure between 0 uMhos and 0 uMhos, consistent with original 1925 RCA, Western Electric, Sylvania, GE, and/or Tung-Sol datasheet specifications for new tubes of this type. The tube must also show no shorts, show a gas current less than 0 mA, and a heater-to-cathode leakage of less than 10 microamps (10 uA). The tube might have mechanical wear or have the label rubbed off - these are very old! Used-testing tubes are available in a separate listing at a significant discount. Every tNOS or Used Good tube you receive from Sound By Doc is guaranteed against failure for 60 days after purchase, an industry extreme!

OPTIONS (use offer feature in Reverb):

Want a regular white box? $1 extra per tube
Want a tube that's packed in its original box? $3 extra per tube
Want the test results recorded on your box, too? $3 extra per tube

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Listeda year ago
ConditionVery Good (Used)
Very Good items may show a few slight marks or scratches but are fully functional and in overall great shape.Learn more
Brand
Model
  • etc. ONE (1) Type 81 antique tNOS AT1000 TESTED Vacuum Tube balloon UX-281 RX281 Half-wave rectifier
Categories
Year
  • 1925-1934
Made In
  • United States

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Sound by Doc

Saint Louis, MO, United States
Joined Reverb:2020

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