National Union NU 813 Vacuum Tube Milspec OEM-BRANDED black glass 6K6GT tubes

OEM-BRANDED black glass 6K6GT tubes was tested on our Maxi-Matcher tube tester with 325 volts on the plates and a bias of -36 volts

They are dead quiet when the CD player is paused and have excellent frequency response

They have an extra mica spacer for vibration suppression

Transconductance measured 50/52 for Tube One and 53/52 for Tube Two where minimum (65%) is 25/25 and 100% is 39/39

National Union NU 813 Vacuum Tube Milspec OEM-BRANDED black glass 6K6GT tubesThis National Union plate 813 output triode was tested on our Paul Hart calibrated for shorts, gas and transconductance. There were no shorts or gas. It measured 64 where minimum is 40 and new is 74. 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 OF SHIPPING