Matched Pair RCA 6FQ7 / 6CG7 Vacuum Tubes NOS NIB 35 Thirtyfive

Matched Pair RCA 6FQ7 / 6CG7 Vacuum Tubes NOS NIB 35 ThirtyfiveThis new old stock, new in box matched pair of RCA 6FQ7 6CG7 dual triodes was tested on our TV7 U for shorts, gas and transconductance. There were no shorts or gas and their readings are as follows: Tube One measured 75 75 while Tube Two measured 77 75 where minimum (65%) is 50 50 and 100% is 77 77. These tubes have steel support rods; ladder plates and side D getters. I played them with adapters (not included) in my Radio Craftsmen RC 2 monoblocks

new in box Sylvania 5U8 tubes tested to spec on our Paul Hart-calibrated TV7/U

these tubes will perform excellently

Charles Treger and Charles Wadsworth

new in box Sylvania 8EB8 8GN8 tube tested to spec on our Paul Hart-calibrated TV7/U

engraved/stamped base

I am playing them with adapters (not included) in my Radio Craftsmen RC-2 monoblocks (with adapters

Tube One measured 57/58 while Tube Two measured 58/58

They have G 3R and W 4R date codes

Transconductance measured an outstanding 92/93 for Tube One and 94/93 for Tube Two where minimum (65%) is 50/50 and 100% is 77/77

There were no shorts or gas and emissions measured as follows:

They measured 86/82

The reference to "Uncle Doug" is a hat tip to The Most Sublime Guitar Amplifier Guru who recommended a significant -- but not-too-large -- difference in plate current draw for just that right amount of push-pull distortion