The 6/30L2 is a general purpose double triode with a screen between the sections. Their main applications are found in television receivers.
Seen side on the screen is visible.
Also donated was a second valve with a broken envelope and this has allowed more detailed photography. The control grid is fine wire on copper supports and the anode lies parallel to the grid. The cathode tube is rectangular in cross section. On the left side of the anode the inner bright surface is seen. The carbonising is for the outer surface only.
The damaged valve with getter holder at the top.
The anodes have holes in the side, probably to aid assembly, but we can see the grid pitch.
The filament is insulated and can be seen to pass several times along the length of the cathode.
The electrodes are connected to the base pins by metal tape that is spot welded at either end.
The thin glass tube envelope is 21 mm in diameter and, excluding the B9A base pins, is 47 mm tall.
References: Datasheet & 1040 Type 6/30L2 was first introduced in 1958.