1 slightly microphonic tube) JRC-12AU7 RCA tall black ribbed plates "D" getter halo tests like new 1950's black sharpie mark over "JRC-12AU7" 9.6ma Gm=2000 10.4ma Gm=2100See more: vacuum tubeShare: Fancy Tweet Tags: 12AU7, blaack plates, D getter halo, ECC82...
vacuum tubes by and large were no longer being produced anywhere on earth. No one really cared, since virtually no consumer products used them anymore. Radio, TV, and Hi-Fi shop owners cussed about the huge racks of tubes they bought (against their better judgment when...