Not ww2, but an interesting fact non the less. It may sound unbelievable, but if you check out the facts on the English Electric Lightning and specifically it's radar system, you'll see it. Apparently, the Mig-21's radar could do the same.
But the Mig couldn't fly to 50,000 in just less than 1 minute!
From Thunder & Lightnings http://www.thunder-and-lightnings.co.../memories.html
They developed a powerful air conditioning system to keep the pilots cool. Semi-conductors would not work above 65°C, so they stuck to using vacuum-tube avionics, even for the radar. It was a monster item of equipment, weighing in at slightly over half a ton. Its pulse-Doppler search and track were basic, but the valve technology and its awesome power gave it unmatched power to burn through the thickest electronic jamming to a range of fifty miles, it would KILL A RABBIT at one kilometre if activated on the ground.
Now that's an awsome fact!!