Matched Pair Sylvania 12B4 12B4A Vacuum Tubes Valves NOS-Testing 9003 Milspec

Matched Pair Sylvania 12B4 12B4A Vacuum Tubes Valves NOS-Testing 9003 MilspecThis new old stock testing, perfectly matched pair of Sylvania 12B4A tubes was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. Tube One measured 46 while Tube Two measured 46 where minimum (65%) is 32 and 100% is 49. Wish I could tell you how they sound, but I don't have any equipment that uses these. WE HAVE SCORES OF THOUSANDS OF VACUUM TUBES. IF IT'S NOT LISTED, WE MAY HAVE IT. PLEASE ALSO

This Tung-Sol 13DE7 tested to spec on our Paul Hart-calibrated TV7/U

MOST OF THE TUBES WE SELL ARE OVER 70 YEARS OLD

new in box Tung-Sol 6SD7GT pentode tested to spec on our Paul Hart-calibrated TV7/U

new in box matched pair of GE 6FQ7 / 6CG7 dual triodes was tested on our Paul Hart-calibrated TV7/U for shorts

This new old stock-testing matched pair of milspec Raytheon black glass VT-107-A / JAN-CRP-6V6-GT output tubes was tested on our Maxi-Matcher 2 with 400 volts on the plates and a bias of -36 volts for shorts

These four RCA and Cunningham number / type 27 tubes tested as low goodand good on our Paul Hart-calibrated TV7/U

There were no shorts or gas and they measure as follows:

PLEASE INSURE THEM

matched pair of GE 6SJ7s was tested on our Paul Hart-calibrated TV7/U for shorts

The remaining two are labeled "1X2B

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

new in box Telefunken PL82 tube tested to spec on our Paul Hart-calibrated TV7/U