Lansdale 12AU7 / ECC82 Vacuum Tube Valve 17MM Black Plates Copper Support Rods Early Production

Lansdale 12AU7 / ECC82 Vacuum Tube Valve 17MM Black Plates Copper Support Rods Early ProductionThis Lansdale (Philco's in house tube manufacturing arm) 12AU7 ECC82 dual triode was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. It measured 77 71 where minimum (65%) is 56 56 and 100% is 86 86. It has shiny 17MM black plates; copper support rods; excellent flashing; a top slanted D getter and L1E or IJI date codes. This is an early production 12AU7 not a 12AU7A like most 12AU7s we see

Transconductance measured 67 in Section One and 65 in Section Two for Tube One and 67/69 in Tube Two where minimum (65%) is 50/50 and 100% is 77/77

They sound great in my Alan Eaton single-ended 45 amplifier (with an adapter

new in box US-made 6BC5 tubes tested to spec on our Paul Hart-calibrated TV7/U

(New US-made 6V6s typically test with plate current from the mid teens to mid 30s with transconductance from 2300 micromhos or so

There were made by Sovtek's predecessor during The Cold War and

They have great bass and sparkling highs and Mann's voice is warm and clear as a bell

S5E and 913 date codes

This United 805 output triode was tested on our Paul Hart-calibrated TV7/U with 180 volts on the plates and a bias of 0 volts for shorts

copper support rods and good flashing

All I can tell you about this new old stock

new in box (For Tube One) matched pair of Unitron 6AK5 tubes was tested on our Paul Hart-calibrated TV7/U for shorts

the shields and bases are threaded and the bases are tapped with mounting holes