Italian Sylvania 12SN7 12SN7GTA Vacuum Tube NOS NIB 8BQ5 Nonal Transconductance: 2200 micromhos Transconductance: 2270

Transconductance: 2200 micromhos Transconductance: 2270 micromhos

These four metal base National Union 6Q7GT tubes tested to spec on our Paul Hart-calibrated TV7/U

This CD plays fine

This new in box JJ 6BQ5 was tested on our Maxi-Matcher with 325 volts on the plates and a bias of -14 volts for shorts

They measured 52

Italian Sylvania 12SN7 12SN7GTA Vacuum Tube NOS NIB 8BQ5 Nonal Transconductance: 2200 micromhos Transconductance: 2270This new old stock, new in box Italian Sylvania 12SN7GTA dual triode was tested on our Hickok 600A for shorts, gas and transconductance. There were no shorts or gas. Transconductance measured a perfectly balanced 2700 2700 micromhos. (New 6SN7s typically test within a standard deviation of 2600 micromhos; minimum (65%) is 1690). It has copper support rods; staggered gray plates; copious flashing and a large, side D getter. I have played it in one of