6N3P

The 6N3P (Russian: 6Н3П) is a Russian-made direct equivalent of the 2C51 vacuum tube. It is slightly larger in size than the American tube.
6N3P was widely used for FM band radio input unit stages (nearly all 1960s Soviet radios with FM band all employed the same input unit on a separate subchassis). Currently, it has some use in DIY preamps. A ruggedized/industrial version of the tube is designated 6N3P-EV (Russian: 6Н3П-ЕВ

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