Matched Pair RCA 6FQ7 / 6CG7 Vacuum Tubes Microphonic Adapters 48 and 48 where minimum

48 and 48 where minimum (65%) is 30 and 100% is 47

new in box US-made 1LN5 tubes tested to spec on our Paul Hart-calibrated TV7/U

new in box GE 12BL6 tubes tested to spec on our TV7/U

It has a diamond in its base with a 135 code

Transconductance was 1620 for Tube One and 1730 for Tube Two where new/nominal is within one standard deviation of 1900

Matched Pair RCA 6FQ7 / 6CG7 Vacuum Tubes Microphonic Adapters 48 and 48 where minimumThis matched pair of RCA 6FQ7 6CG7 dual triodes was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas and transconductance measured as follows: Tube One: 54 68 Tube Two: 58 65 Bogey: Minimum (65%) is 50 50; 100% is 77 77 Physical Characteristics: Bases: N A Bottles: tall Date Codes: none EIA Factory Codes: none Getters: mid bottle, D Flashing Quality: excellent Mica Spacers, Bottom: crenelated,