National Union NU Number / Type 80 #80 Vacuum Tube Rectifier Black Plate ST Shoulder Shape June 16 2025 The Hickok-tested 6AV5 tested 4200

The Hickok-tested 6AV5 tested 4200 micromhos where new/nominal is 3900

came from an excellent lot and should work fine

GM-BRANDED 6SK7 tested as good on our Paul Hart-calibrated TV7/U

I am playing it in one of my ArtSound monoblocks as I write and it is absolutely silent

This historical recording sounds pretty good

National Union NU Number / Type 80 #80 Vacuum Tube Rectifier Black Plate ST Shoulder Shape June 16 2025 The Hickok-tested 6AV5 tested 4200This National Union number 80 rectifier tube was tested on our Paul Hart calibrated TV7 U for shorts, gas and emissions. There were no shorts or gas. It measured 47 50 where minimum (65%) is 40 40 and 100% is 62 62. WE HAVE SCORES OF THOUSANDS OF VACUUM TUBES. IF IT'S NOT LISTED, WE MAY HAVE IT. PLEASE ALSO SEE OUT ETSY SISTER SITE "LOWTECHTWOO" AND OR CALL OR TEXT US AT 202 372 6931 IF YOU DO NOT SEE WHAT YOU NEED OR HAVE ANY QUESTIONS. 1. MOST FORMS