The ACT25 also had a CV number of CV436 is an air cooled external anode triode. The prototype was the E1996 from M-OV. It was designed for RF power generation in the UHF region between 500 MHz and 1 GHz.
This triode was designed for forced air cooling of the anode. The maximum dissipation is 450 Watts.
Our other ACT25 exhibit has the copper and brass external sections as pristine as new unlike this one.
The anode end showing the central anode with folded cooling fins within the outer collar. The large grid connection (86 mm diameter) is perforated to allow the passage of the cooling air towards the anode.
The cathode connection, copper ring, can be seen through the glass to project towards the grid. The construction is planar - the emitting surface is a flat disc close to the grid mesh and the anode will be a solid mass the other side of the grid and machined at the end to a flat disc.
The heater connection at the top of the valve together with the identification.
The disc seal envelope is 51 mm in diameter, and including the base pins is 130 mm tall.