The 6P1 is an audio output beam tetrode. It was introduced in the mid 1950's and obsolete a decade later.
With a cathode resistor of 180 Ω and an anode load of 5,000 Ω it would produce 4.2 Watts at 7% distortion. It shares the pin arrangement with the 6V6 family.
The anode seam is along the working face.
The at the grid ends the anode is cut away. The beam forming plates are seen either side of the central cathode and grid assembly.
The electrodes in close-up. The control grid passes flat across the width of the cathode but the screen grid is a helix.
The wide glass tube envelope is 29 mm in diameter, and excluding the IO base pins is 75 mm tall.
Reference: 1040. Type 6P1 was first introduced in 1955. See also1955 adverts.
