Matched Quad RCA 6FQ7 / 6CG7 Vacuum Tubes 6K6 Black And Silver This lot of four North

This lot of four North American-made number 78 tubes was tested on our Paul Hart-calibrated TV7/U for shorts

67 and 74 where minimum (65%) is 53

For sale are three new old stock

These tubes have tall bottles

Matched Quad RCA 6FQ7 / 6CG7 Vacuum Tubes 6K6 Black And Silver This lot of four NorthThis matched quad of RCA 6FQ7 6CG7 dual triodes was tested on our TV7 for shorts, gas and transconductance. There were no shorts or gas and their readings are as follows: They measured 66 59, 68 58, 68 62 and 70 60, respectively, where minimum (65%) is 50 50 and 100% is 77 77. These tubes have steel support rods; ladder plates; side D getters and excellent flashing. As I write, I am playing them with adapters (not included) in my Radio Craftsmen RC 2