Where are electrical engg related companies mostly in USA?

Answer 1

Primarily in Silicon Valley, the San Jose area of N. California.

Also in the Austin and Dallas areas of Texas; Irvine, California; Boulder, Colorado; Boston area off rt128; a bit in Chicago; Some in Tampa, Fla, and Melbourne, Fla. A bit in Research Triangle Park, North Carolina; and some along the Beltway of Washington, D.C.