[Arran]

Well, I don't have much respect for de Forest. He did invent the audion (triode vacuum tube), but didn't really understand how it worked. Armstrong did, and put it to work with his regeneration patent. de Forest somehow came up with the idea that he was the true inventor of regeneration and, after several court cases, finally found a court sympathetic to his cause which unjustly cost Armstrong his first great invention.

Then de Forest teamed up with Theodore Case to research sound-on-film technology. Case was the true inventor here while de Forest took all of the credit. Case eventually broke ties with de Forest and went on to perfect his sound-on-film technology, which he sold to Fox.

According to Ken Burns' Empire of the Air documentary, an arrangement was once made to send a postcard to de Forest as a publicity stunt, addressed only to "The Father of Radio, (I believe) Hollywood, California." The postcard was sent back, marked "Addressee unknown."

Edit: I almost forgot - One of de Forest's "inventions", the spade detector, infringed upon the patents of Fessenden's electrolytic detector. Fessenden sued, and unlike Armstrong, he won.

Ron;
  I found out later that Empire of The Air was somewhat of a hatchet job on Lee Deforest, there is a special addition of Radio Craft from the 1940s that tells the story of what was involved in the development of the Audion, it was definitely not a case of Deforest simply grabbing a Fleming valve one morning and deciding to stuff a grid into it. What's more it mentioned all of the other people involved such as McCandless, who later went on to work for Westinghouse.
I know it may make for good entertainment portraying white hats and black hats in a story like this, Armstrong, the hero in the white hat, Deforest, the hustler, and David Sarnoff as the Darth Vader of the story, but what seems like black and white was closer to being on the grey side.

Regards
Arran