12B4

The 12B4 is a triode with 5.5 W maximum plate dissipation, 1000 V peak plate voltage, and and 105 mA peak cathode current. It has a B9A (Noval) miniature 9-pin base.

parallel 12B4s (center left) as pass elements in 585 power supply

The 12B4 is used in the 551 and 555, and as a pass tube in the power supply of the 513, 581 and 585.

Data

• 12B4A Datasheet (PDF)
• 12B4 @ radiomuseum.org

Pictures

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  12B4 Tube