(!!) (Recommended Pair) 12HG7=12GN7A Sylvania coated glass NOS 1970 era (52ma and 55ma)
$ 19.99
1 pair) 12HG7=12GN7A Sylvania coated glass NOS
1 tube) 52ma Gm=29,200
1 tube) 55ma Gm=31,300
(12HG7=ruggedized frame-grid version of 12BY7A, uprated to 10 watts)
Pentode
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