History of radar 

Thanks for the reply.  I have tried both Radar and radar but neither works for me.  When I previewed this entry just now, the heading appears in blue, but when I click on it, it tells me that an article does not exist.  Am I losing my metaphorical marbles already, or is there something wrong? 
That is very strange - both work flawlessly for me. Have you tried clearing your browser cache? (Open the page in question, then click CTRL+refresh (CTRL+F5 in Internet Explorer)). That is indeed odd. —  | (talk)