The DO26 is an audio output triode from Mullard. It has a lower impedance than the DO24 and thus a higher output. The anode dissipation is around 25 Watts.
The filament passes through the valve six times.
The main characteristics and Mullard name are on the dome.
The original early 1030s box.
The main operating details are printed on the box.
The top of the box.
The valve is retained by a shaped card interior.
The images have been taken from an ebay listing.
The balloon envelope is mm in diameter and, excluding the B4 base pins, is mm tall.
