If you work with RF - this is a good site to visit. Lots of good RF-related information and tools.
RF Cafe is a unique portal of RF, microwave, wireless, and other engineering resources. Vast collection of equations, references and conversions for electrical, mechanical, physical, and mathematical fields. Links for vendors, app notes, test notes, ham radio, magazines, books, active forums, patent and communications standards, technical crossword puzzles, quizzes, and much more.
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