RCA Black Plate 5963 / 12AU7 / ECC82 Vacuum Tube Industrial-Grade For Your Univalve Or Bottlehead RCA 6160 6365 new in box GE 5

new in box GE 5 Star 5663 premium tube tested to spec on our Paul Hart-calibrated TV7/U

new in box GE 20AQ3 / LY88 tube tested to spec on our Paul Hart-calibrated TV7/U

Three are GE and two are Sylvania

Transconductance measured 20 where minimum (65%) is 16 and 100% is 25

RCA Black Plate 5963 / 12AU7 / ECC82 Vacuum Tube Industrial-Grade For Your Univalve Or Bottlehead RCA 6160 6365 new in box GE 5This RCA Black Plate, industrial grade 5963 12AU7 ECC82 tube was first tested on our Paul Hart calibrated TV7 U as a 5963 as well as a straight 12AU7 and then tested on our Maxi Preamp II for shorts, gas, noise, transconductance and gain. There were no shorts, noise or gas and they tested as follows: On the TV7 U with bias set to 30 (5963) it measured 66 56 where minimum (65%) is 56 56. On the TV7 U with bias set to 24 (12AU7) it measured 86 73 where