RCA Clear Top 12AU7 ECC82 Vacuum Tube For Your Bottlehead Or Univalve NOS-Testing Westinghouse NIB copper support rods and round

copper support rods and round mica spacers

I will update this listing

There is some marking in the first twenty pages or so

This matched pair of Westinghouse black plate 12AU7A / ECC82 dual triodes was tested on our Paul Hart-calibrated TV7/U for shorts

It is dead quiet when the preamp is muted and has excellent frequency response and dynamics

RCA Clear Top 12AU7 ECC82 Vacuum Tube For Your Bottlehead Or Univalve NOS-Testing Westinghouse NIB copper support rods and roundThis new old stock testing RCA clear top 12AU7 dual triode was tested on our Maxi Preamp II for shorts, gas, noise and gain. There were no shorts, noise or gas. Measurements are as follows: Noise dynamic range: 84. 6 dB 84. 9 dB; Transconductance: 1264 1360 and Gain (Mu): 16. 1 17. 2 New 12AU7s typically test within a standard deviation of 17 17 for gain. The noise floor on this tester is 92dB 92dB. There is no transconductance reference reading and