Matched Pair GM-Labeled National Union NU 6V6 6V6GT 6V6GT/G Black Glass Vacuum Tubes NOS-Testing April 25 2022 new in box GE 25Z5

new in box GE 25Z5 tube tested to spec on our Paul Hart-calibrated TV7/U

They tested 54

This Westinghouse 6AC7 tube tested to spec on our Paul Hart-calibrated TV7/U

it was made in Yugoslavia

Matched Pair GM-Labeled National Union NU 6V6 6V6GT 6V6GT/G Black Glass Vacuum Tubes NOS-Testing April 25 2022 new in box GE 25Z5This new old stock testing matched pair of GM LABELED, black glass 6V6GT G output tubes was tested on our Maxi Matcher 2 for shorts, gas and transconductance. There were no shorts or gas. Plate current measured 33. 3 milliamps and transconductance was 2490 micromhos for Tube One. Tube Two measured 33. 6 2910. (New US made 6V6s typically test with plate current from the mid teens to mid 30s with transconductance from 2300 micromhos or so.) They have