The CV1673 is a receiving triode. The anode is shaped from pressed sheet that is formed with ridges for extra rigidity. The commercial valve HL2 was introduced in 1931. The CV specification says that the valve was also known as POVT105 as a GPO valve.
The shape of this valve matches the HL2 from Tungsram.
The identification code and the anode side view.
The anode is left bright and has ridges pressed into the thin nickel sheet to add mechanical strength.
The top of the envelope enhanced image showing the grid, top mica, filament and filament tension spring.
The classic envelope is 28 mm in diameter and, excluding the B4 base pins, is 70 mm tall.
References: Data-sheet & 1040 Type CV1673 was first introduced in 1931. See also1931 adverts.
