One Tested UX 281 81 RCA Radiotron Globe Balloon Audio Receiver Power Vacuum Tube 

Country of origin: USA

Production era: Estimate 1920-1930s

Model:   UX 281   81

Manufacturer: RCA  Radiotron 

Type:   rectifier

Plate type: black with support rods

Filaments:  hanging V with a glass insulation rod 

Base type:  Engraved UX 4 pin plus a side locking tab

Getter frame: solid disk

Getter flash: circular side 

Glass: clear

Stencils: excellent

Condition:  excellent  

Usage (estimate):  minimal

Quantity:  1

Please review the photos for more detail

Test results:

       Excellent strong test result for Emissions: 48

For Gm, the suggested minimum value is: 28  

Shorts: None detected

For testing, a calibrated Triplett 3444A tester was used

Compatibility: Suitable for vintage tube-based equipment, ideal for use in audio amplifiers, power amps, and general tube equipment

The tubes will be carefully packed to ensure safe shipping

Estimated delivery time within the USA is 3 to 7 business days

Standard shipping service is US Postal 1st class

Shipping is combined when applicable

Please feel free to contact us if you require any additional information