Here are comparative blast radiuses and yields of some nuclear weapons. Note that for example Tsar Bomba (56MT), although having almost 4 times the yield of Castle Bravo(15MT), has less than twice the blast radius of the latter. Point of super strong thermonuclear weapons was more in being able to deliver immense power to a single point rather than having large blast radius.
In other words: to have a nuke, capable of taking out two adjacent radars with a single hit, you would have trade up 20 or 30 conventional nukes for it.








