Matched Pair Sylvania 6F6 6F6G Vacuum Tubes Black Plates Clear Shoulder / ST Bottles RCA Octal They tested 49/48

They tested 49/48

Fortunately the libretto is present and in great shape

new in box Mullard UBC41 tube tested to spec on our Paul Hart-calibrated TV7/U

even though they test on the cusp

I do not have the ability to test them and they are being sold as-is with no returns

Matched Pair Sylvania 6F6 6F6G Vacuum Tubes Black Plates Clear Shoulder / ST Bottles RCA Octal They tested 49/48This matched pair of Sylvania 6F6G tubes was tested on our Maxi Matcher 325 volts on the plates and a bias of 36 volts for shorts, gas and transconductance. There were no shorts or gas. Tube One drew 26. 2 milliamps' plate current and measured 1910 micromhos while Tube Two measured 27. 4 1930 where new 6F6s measure from approximately 2000 micromhos with plate current draw in the 20s. These tubes have black, three hole plates; copper support rods;