The CV2797 is a rugged double beam tetrode designed for VHF RF power amplifiers. The CV specification describes the valve as a robust version of the QQV06-40.
The heater is centre tapped to allow for 12.6 or 6.3 volt operation.
In use the designer would take care to keep the grid circuitry below the chassis with the anodes being connected to circuits remote from the input. This way undesirable feedback could be avoided.
The European design of internal capacitors for neutralisation is incorporated. Such neutralisation prevented parasitic oscillations during operation in a well designed layout.
The anodes are finned for good heat dissipation and clearly separated from the central structures, the anodes are brought out to pin like top caps. The lettering within the circle is EEVC which we take to mean English Electric Valve Company.
Following the European pattern, a central flat cathode is surrounded by a split control grid (one half per valve), a common screen grid is wound next. The back of the beam forming plates can be seen.
The wires at the tops of the control grids are the neutralising capacitors.
The wide glass tube envelope is 44 mm in diameter and, excluding the B7A base pins, is 73 mm tall.
References: Data-sheet & 1040. Type CV2797 was first introduced in 1964. See also1964 adverts.