DaveA
I can't locate the UK link about ATC history at the moment but here are a couple to be going on with:-
http://mit.edu/6.933/www/Fall2000/mo...ackground.html
http://spacecom.grc.nasa.gov/icnscon...2-1_LaFrey.pdf Needless to say it was all invented 'here' (does mention Chain Home though). Happy to have a go at any 'dumb questions'!
Like airac said it's all very s-l-o-w.
RR