Tested Matched Pair of RCA 6SN7GT Tubes.
Date Codes 352 and 430.
Tubes are closely matched for Gm testing (see below) and internal structure - they are identical.
Black staggered plates with copper grid posts and bottom square D getters.
One tube base has worn wording with some minor bubbling of the bakelite near the bottom lip - see photo 4. Obviously, this doesn't affect performance in any way.
Tested on a calibrated Hickok TV-10 military tube tester with no shorts and no leaks with the following results:
Gm Test = 3000-2875 and 2875-2750 micromhos
Minimum pass/good = 1650-1650
Also performance tested in-circuit through a Class A amplifier with no microphonics detected.
~ Please view all 5 photos ~
