The CV82 UHF triode from the 1930s uses disc seal construction but does not then make use of a mesh grid to divide the filament from the anode. The so called lighthouse layered valves came later. The copper grid disc is 48 mm in diameter.
The CV82 specification was based on the S27A.
The outer envelope fused to the pinch stem with the evacuation tube in the centre. The heater/cathode connects via the flying leads.
The folded anode connects to the top cap. The folding gives a large total surface area whilst presenting only a small face to the electron stream.
The control grid has been conventionally wound across two support wires and then one side has had the wire shaved off. Through the grid wires can be seen the flat oxide coated cathode.
The cathode tube with the insulated heater wires entering.
Not the best image. The heater wires can be seen to be spot welded to the connecting tape - this suggests that the base wire is not tungsten.
The single sided grid.
The folded anode.
The wide glass tube envelope is 30 mm in diameter and, excluding the base wires, is 66 mm tall.
