NEC 6SN7 6SN7GTB Vacuum Tube NOS-Testing Leo Sayer GE-branded 6DA5 / EM-81 indicator

GE-branded 6DA5 / EM-81 indicator tube tested to spec on our Hickok 800

see-through holes on the plates

We also have Soviet-era tubes to go with it

This matched pair of GE black plate 6005 / 6AQ5 output tubes was tested on our Paul Hart-calibrated TV7/U for shorts

new in box matched pair of Ken-Rad JAN-CKR-2C22 / 7193 milspec triodes was tested on our Paul Hart-calibrated TV7/U for shorts

NEC 6SN7 6SN7GTB Vacuum Tube NOS-Testing Leo Sayer GE-branded 6DA5 / EM-81 indicatorThis 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