The 15R is a matching rectifier for the 15E UHF pulse Radar triode. Eimac designed the valves in 1940 for the first American airborne Radar.
The peak current required by the triodes could reach 20 Amps and the figure of 30 mA is the average value. The peak pulse power was 5 kW at a repetition rate of 400 Hz and a duration of 2 μS The Va figure above is the PIV rating.
The manufacture of the rectifier is the same as the triode but without the grid cage.
The etched lettering and the evacuation pip on the side of the glass. The anode is supported by an extended length of plain glass.
The open anode reveals the helical filament with central support and top connection.
The two base bins.
The box is dated 1943. It is 77 mm square and 92 mm tall. The valve is held by shaped trays that keep it away from the external surfaces of the carton.
The wide glass tube envelope is 35 mm in diameter and, excluding the base pins, is 58 mm tall.
Reference: Private communication. Type 15R was first introduced in 1940. See also1940 adverts.
