The CV53 is a UHF triode designed for grounded grid use and the prototype was the S26A. The commercial equivalent is the 3A/146J from STC.
The grid is connected to the flange but is wound on supports attached to the cathode assembly. In this respect it shows the development of the final form of the disc seal triode where the grid is a mesh attached to the flange and the cathode assembly and also the anode are positioned either side of the mesh.
The heater is connected to one side of the oxide coated cathode. The cathode is coated on one side only.
The valve seen from the top showing the folded box section anode. The underside of the box is flat.
The anode dissipation in natural air was 2 Watts. The amplification factor (μ) is 100 and to derive the operating bias the cathode resistor was specified as 150 Ohms.
The electrodes seen across the 48 mm diameter flange.
The wide glass tube disc seal envelope is 27 mm in diameter and, excluding flying leads is 65 mm tall.
References: Datasheet & 1040. Type CV53 was first introduced in 1947.