1960s RCA 12AX7A (ECC83 12AX7-A) Tube - Hickok TV7B tests @ 55/59, min:32/32

Type 12AX7A (ECC83) vacuum tube. (Triode#1 / Triode#2). Hickok TV-7B/U tested. Hickok TV-7B/U is a mutual conductance (Gm) type tube tester. One tube,circa 1960s ,USA madeby RCA. Tube features gray-Ladder-plates and a 'Halo-Ring' getter on top.

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