If you get the "Sorry, the file cannot be displayed. There seems to be a technical issue ..." error when trying to view an image, a workaround is to click on the cog icon in the upper right side of the media viewer, and then select "Disable Media Viewer". We are aware of the problem and are looking for a solution.
The 6U8 (European equivalent ECF82) is a triode and pentode in a single tube with a B9A (Noval) miniature 9-pin base.
Tek part number: 154-0033-00