With this tube we have taken the legendary 300B in production. All critical parts, like grids and plates are constructed of hard metal for higher reliability and reproducible quality. This tube is a direct replacement for the WE300B, and features a center tapped filament as well. (See Note6)

Features

• Gold plated Grid. (Note 8)
• Center tapped filament
• Soft rubber suspended tube base
• 4 circular cooling plates
• Hard metal Construction (Note 1)
• Two extra large getters
• Hand blown Glass bulb
• Anti-microphonic plate- and grid suspension
• These tubes are shipped in a high quality dual box
• Tube printing with real gold (metal), red color is glass burned into the glass
• Machined, solid tube base pins for highest contact precision. YAMAMOTO tube sockets highly recommended.
• Gold plated pins, black ceramic socket. (White bottom.)

• Note 1) Hard-metals can be used in electron tubes, though these are more difficult to use, and more costly than the classical nickel. Hard metal plates have a more precise plate distance, and do not change shape when heated, or at mechanical shock. This ensures reproducible tube parameters, and long term stability. Wolfram grids allow the most precise grid wire distance, because wolfram is an extreme hard metal. Best grid geometry ensures uniformity and linearity of the tube curves.
• Note 2) Individual Test data, such as: Matching Data, Grid Current, Vacuum, Filament Current, etc., are on the Certificate that is on the outside of the tube box. Each tube is numbered from the inside, with a metal Tag
• Note 3) Plate Curves: Made with the Sofia Digital Curve tracer. Plate curves with courtesy of AMR
• Note 4) We recommend the same values as Western Electric in their 1950 Datasheet.
• Note 5) The Western Electric 1950 Datasheet says 36 Watt maximum dissipation. Later datasheets say 40 Watt. Though 40 Watt is possible, this is a peak value only, and no normal working point. When you intent to get the "maximum" out of a 300B, and operate this tube at the limits of safe operation, it is a better idea to use the 300B-XLS in such a case.
• Note 6. Some manufacturers claim to be the only one with a center tapped filament, but this is not longer true. At EML we build since several years now all triodes center tapped, not only the the 300B.
• Note 7) Don't experiment with lower filament voltage, and expect better lifetime. If it was that easy, we would make them like this ourself. The specified filament voltage is the one for best lifetime.
• Note 8) Gold plated grids have a few advantages. Amongst other this will give better bias stability of the tube, some protection against accidental overload, and better linearity of tube curves.