The CV2799 is a double beam transmitting tetrode following the European pattern of a central flat cathode surrounded by a split control grid (one half per valve), a common screen grid and separate anodes. 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 and all external connections are gold plated.
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.
Something not seen on earlier production batches - a health and safety warning!
The bright beam plates in the centre and the screen grid just visible through the rectangular aperture of the beam plate.
The sintered glass top reduced the likelihood of the anode pins cracking the envelope. The sintering process produces the extra strength in the glass.
The base is also made from sintered glass. Note how the gold plating has been scraped off the pins by insertion and removal from the B7A socket.
The wide glass tube envelope is 43 mm in diameter and, excluding the B7A base pins and top pins is 53 mm tall.
