Sylvania 12SG7 Vacuum Pentode RF/IF-Stage

The 12SG7 is a 12.6 Volt version of the 6SG7 semi-vari mu pentode. The pins are compatible and the ratings are the same.

The 12SG7 is a variable μ design with a medium gain. It was obsolete by the early 1960s.

The thin metal tube envelope is 25 mm in diameter, and excluding the IO base pins, is 50 mm tall.

The 12SG7 was first introduced in 1940.