Matched Trio General Electric GE 12HG7 12GN7 12GN7A Vacuum Tubes NOS NIB Fat Bottles 6K6GT Black Glass Transconductance measured 50/52 for Tube

Transconductance measured 50/52 for Tube One and 53/52 for Tube Two where minimum (65%) is 25/25 and 100% is 39/39

there are no reference numbers on it

These four National Union type / number 41 tubes tested as follows on our Paul Hart-calibrated TV7/U:

new in box Cunningham 14F7 tube tested to spec on our Paul Hart-calibrated TV7/U

steel support rods and excellent flashing

Matched Trio General Electric GE 12HG7 12GN7 12GN7A Vacuum Tubes NOS NIB Fat Bottles 6K6GT Black Glass Transconductance measured 50/52 for TubeThis matched trio of GE 12HG7 tubes was tested on our Paul Hart calibrated TV7 U (on the 12BY7 setting) for shorts, gas and transconductance. There were no shorts or gas and they measure as follows: 75, 78 and 80 where minimum (65%) is 46 and 100% is 71. These tubes have anode radiators for cooler operation and longer tube life; side O getters; solid saucer getters and excellent top and side flashing. WE HAVE SCORES OF THOUSANDS OF VACUUM TUBES. IF