NOTES
* I do not yet know any correct designation for this tube base type; "SK‑207" is the part number of a compatible socket.
Both pins indicated above as "A" are connected internally to the anode mesh.
Arrow points away from tube outline indicating top of symbols for end-viewed tubes, points toward tube outline indicating direction of viewing for side-viewed tubes.
Pins are shown as looking at the base of the tube; i.e. "bottom view" - with lead spreader/standoff in place.