Matched Pair Sylvania 6K6 6K6GT Vacuum Tubes Valves US-Made Gebraucht This new old stock

This new old stock

All four tubes' diodes tested fine as well

This Raytheon 6JM6A tube is new old stock

All tested to spec on our Paul-Hart-calibrated TV7/U

new in box GE 6FM7 tested to spec on our Paul Hart-calibrated TV7/U

Matched Pair Sylvania 6K6 6K6GT Vacuum Tubes Valves US-Made Gebraucht This new old stockThis matched pair of Sylvania MANUFACTURED, Philco LABELED 6K6GT tubes was tested on our Maxi Matcher 400 volts on the plates and a bias of 36 volts for shorts, gas and transconductance. There were no shorts or gas. Tube One drew 18. 4 milliamps' plate current and measured 1460 micromhos. Tube Two measured 19. 5 1710. New nominal is within one standard deviation of 1900. These tubes have copper support rods; rectangular mica spacers; anode radiators