The TY2-125 is a power triode for use up to 200 MHz and it has an anode dissipation of 136 Watts when adequately cooled.
Two valves operated in Class B as an audio modulator could supply 700 Watts at 5% distortion.
The distinctive anode with side lobes.
The top of the anode with the four fixing points to the top cap. The anode does not have a lower fixing. The grid is clearly seen but not the filament. The thoriated tungsten filament is held by stout rods top and bottom. The filament is a short section of helix located at the centre part of the anode.
The base of the anode with the thick filament support seen within the grid. The lower disc is a screen.
The wide glass tube envelope is 60 mm in diameter, and excluding the B5F base pins is 106 mm tall.
Reference: Data-sheet. Type TY2-125 was first introduced in 1957. See also1957 adverts.