4 US-Made 7B7 Vacuum Tubes Lot Of Four Steven Curtis

4 US-Made 7B7 Vacuum Tubes Lot Of Four Steven CurtisThis lot of four US made 7B7 tubes was tested on our Paul Hart calibrated TV7 for shorts, gas and transconductance. There were no shorts or gas. Transconductance measured 41, 42, 44 and 47, respectively, where (65%) is 43 and 100% is 66. They have mica snubbers for increased vibration resistance and lowered microphonics and great flashing. WE HAVE SCORES OF THOUSANDS OF VACUUM TUBES. IF IT'S NOT LISTED, WE MAY HAVE IT. PLEASE ALSO SEE OUT ETSY SISTER

Tube One measured 1930 micromhos

Tube One measured 54 while Tube Two also measured 54

Sorry about the boxes

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

new in box Sylvania 8LT8 tubes tested to spec on our Paul Hart-calibrated TV7/U

This matched quad of new old stock

new in box Sylvania 6BX7GT tube tested to spec on our Paul Hart-calibrated TV7

Tube One measured 57/63 while Tube Two measured 60/61 where minimum (65%) is 38/38 and 100% is 58/58

new in box Sylvania 5BC3 tested to spec on our Paul Hart-calibrated TV7/U

9 milliamps with a transconductance of 2390 micromhos while Tube Two measured 21

They have tall bases

They measured 85/66 for Tube One and 85/70 for Tube Two where minimum (65%) is 57/57 and 100% is 88/88