The CV8067 is a variant of the QQV03-20A from Mullard and is a double beam tetrode transmitting valve. How it differs from the original CV2799 is not easy to determine. The only obvious difference is the absence of sintered glass in the top and bottom plates.
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 two beam forming plates can be seen either side of the central assembly. 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 heater runs at 6.3 Volts when both halves are in parallel or 12.6 Volts when in series. For 6.3 volts pins 1 & 7 are connected together with pin 5 as the other end. For 12.6 Volt operation the voltage is connected to pins 1 & 7 with pin 5 left unconnected.
In addition to use as transmitter power amplifiers the upper frequency of 600 MHz made them popular for frequency multiplication.
The anode plate hang from the top glass. Visible in the centre is the common screen grid. The single sided control grids are not visible.
The B7A base pins and clear glass base.
The top glass with anode pins and supports for the top mica holding the central electrodes firmly in place.
The wide glass tube envelope is 43 mm in diameter and, excluding the B7A base pins and top pins is 47 mm tall.
