The EL13 from Telefunken is an audio output pentode and the naming convention directly relates to Philips/Mullard. The output power will be low with an anode current of 20 mA and so the output stage of a domestic receiver is the probable design purpose for this valve. The EL8 was identical electrically but on a Ct8 base.
Our exhibit is new and came boxed. As is to be expected from Telefunken the writing on the box is in German.
The pin connections conform to the Philips style of numbering.
The inside of the tubular envelope is coated.
The control grid is wound on copper supports and has a cooling fin attached. The anode is cylindrical and the suppressor grid is in fact just two vertical rods that are bridged together above the top mica.
The Footless base.
The wide glass tube envelope is 31 mm in diameter and, excluding the Footless base pins, is 82 mm tall.
References: Datasheet. Type EL13 was first introduced in 1949.