Matched Pair Sylvania 6V6 6V6GT Vacuum Tubes Silver And Gray NOS-Testing National NOS NIB This Sylvania 6SF7 tube tested

This Sylvania 6SF7 tube tested to spec on our Paul Hart-calibrated TV7/U

48 and 57 were minimum (65%) is 36 and 100% is 55

Transconductance measured 40

65 and 79 where minimum (65%) is 45

Matched Pair Sylvania 6V6 6V6GT Vacuum Tubes Silver And Gray NOS-Testing National NOS NIB This Sylvania 6SF7 tube testedThis matched pair of Sylvania silver and gray 6V6GT output 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 30. 6 milliamps with a transconductance of 3060 micromhos while Tube Two measured 31. 3 2640, (New US made 6V6s typically test with plate current from the mid teens to mid 30s with transconductance from 2300 micromhos or so.) These