NEC 6SN7 6SN7GTB Vacuum Tube NOS-Testing Leo Sayer new in box Ken-Rad 6R7

new in box Ken-Rad 6R7 tube tested to spec on our Paul Hart-calibrated TV7/U

We also have Soviet-era tubes to go with it

see-through holes on the plates

They measured 44 and 48 where minimum (65%) is 30

NEC 6SN7 6SN7GTB Vacuum Tube NOS-Testing Leo Sayer new in box Ken-Rad 6R7This new old stock testing NEC MANUFACTURED, Channel Master LABELED 6SN7GTB was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. Transconductance measured a perfectly balanced 81 81 where minimum (65%) is 50 50 and 100% is 77 77. This tube was made in Japan for Channel Master in the early to mid late 1970s and has copper support rods; a short base; a tall bottle; gray plates; a top D getter