The CV4020 (commercially the 6073) shows the final design format of the valve voltage stabiliser. The CV4020 would strike at 165 Volts and the regulation would be 5 Volts for changes in current of 5 - 30 mA.
The QTL logo.
The cathode cylinder with a central rod anode.
The thin glass tube envelope is 17 mm in diameter and, excluding the B9A base pins, is 59 mm tall.
References: Data-sheet & 1040. Type CV4020 was first introduced in 1955. See also1955 adverts.
