Sensibly equivalent¶ to:
The CV5121 and its commercial equivalent the 6870 are described by Brimar as 'Trustworthy' presumably this denotes a special quality valve.
The design purpose of this high slope valve is RF power or video amplification.
The anode is blackened to assist radiating the heat generated when operating, this can be as much as 6 Watts. The anode has holes opposite the grid support rods at the point of minimum current flow.
The thin glass tube envelope is 20 mm in diameter, and excluding the B9A base pins is 60 mm tall.
References: Data-sheet, 4053 & 4004. Type CV5121 was first introduced in 1959. See also 1959 adverts.
Absolute Maximum Operating Conditions¶
Updated October 16, 2013.