Complex sentence: The head of the Microwave Committee was Alfred Lee Loomis, the millionaire physicist, who decided to create a laboratory, selected a site for it, chose a suitably discreet and ambiguous title for it and even funded it, until the Federal administration was set up.
Split into simpler sentences: The head of the Microwave Committee was Alfred Lee Loomis, the millionaire physicist, who decided to create a laboratory. He selected a site for it, chose a suitably discreet and ambiguous title for it and funded the construction, until the Federal administration was set up.