The 810 is a power triode designed for class B service as a transmitter modulator or audio power amplifier. For an input power of 13 Watts a pair of 810's can deliver up to 725 Watts output.
The data-sheet indicates use as an RF power amplifier and/or oscillator. Probably only at HF to 30 MHz.
The RCA logo on the base and the Type designation etched into the glass within the characteristic octagon.
In red on the base are the words 'Made for Canadian Marconi Company'. Note the bands around the pinch stem to hold the electrodes secure. These are hand made valves.
The side grid connection and graphite anode.
The top ceramic insulator: the filament tension springs are of a substantial wire gauge. The thoriated tungsten filament is not visible.
The pinch components. The thickness of the graphite anode is about 1.5 mm and as this is an American product a thickness of 1/16 of an inch is probable.
The internal construction is not visible due to the mica sheets placed top an bottom of the anode.
The wide glass tube envelope is 64 mm in diameter, and excluding the base pins is 205 mm tall.
Reference: Data-sheet. Type 810 was first introduced in 1946. See also1946 adverts.
