This is Lee deForest, a radio pioneer who invented, among other things, the audion vacuum tube, used in early radio amplification. He also found himself constantly involved in lawsuits and hostile takeovers of his businesses, partly because of his own lack of any real business sense, partly because he sometimes surrounded himself with shady characters, and partly because he patented a few things that in the proper light might seem to have been “borrowed” from other inventors.

In 1906 he was doing well making radio receivers for the military that used a certain detector that bore some similarity to one patented by another radio pioneer, Reginald Fessenden, who sued deForest. Fessended won, and deForest had to scramble to find another detector. He had invented but not perfected the audion. Fortunately for him retired Army general Henry Harrison Chase Dunwoody, who was a vice president of deForest’s company, had just invented the carborundum radio detector, arguably the first patented practical semiconductor device. It didn’t work very well, but they hired a consultant, G. W. Pickard, who redesigned it and made it a very successful detector. It saved the company, but deForest was kicked out anyway. the only thing he was able to take with him was the patent for his audion tube, which the directors deemed worthless. Eventually it would make a fortune for deForest.

Very little is known about the relationship between deForest and Dunwoody, or the details of how the carborundum detector was discovered. If Dunwoody kept notes they are lost, and deForest barely mentions Dunwoody in his writings (not surprising; deForest was a shameless self promoter). He did write one letter in his later years regretting that Dunwoody, long deceased, never got the credit he deserved.

I have been searching for years for any links between deForest and Dunwoody to flesh out the story. Members of Dunwoody’s family have searched in vain (so much appreciation to them!), deForest’s works at the Library of Congress have been scoured, but nothing. I had just about given up when I found, by accident, that the History San José archives houses a large collection of deForest materials, including his research notes from the period. I hadn’t noticed them before because they had been stored until 1991 in one archive  then moved, effectively without a home, until they were added fairly recently to the History San Jose collection. The archivist was kind enough to offer to dig through the collection to see what he could find. Stay tuned…