As early as 1977, HP started manufacture of the HP856x spectrum analyzers to enhance its RF ability meters and sensors capable of measuring signals in excessive of twenty GHz. HP also manufactured configurable chassis centered sweep turbines able to creating indicators to 20 GHz. Other T&M solutions of enough time https://borna.news/fa/news/2055964/%D8%B3%D8%B1%D9%88%D8%B1-hp-%DA%86%DB%8C%D8%B3%D8%AA-%D9%88-%DA%A9%D8%A7%D8%B1%D8%A8%D8%B1%D8%AF-%D9%87%D8%A7%DB%8C-%D8%A7%D9%86-%D8%AF%D8%B1-%D9%BE%D8%B2%D8%B4%DA%A9%DB%8C