As early as 1977, HP began production of the HP856x spectrum analyzers to enhance its RF electricity meters and sensors able to measuring signals in excess of 20 GHz. HP also manufactured configurable chassis based sweep turbines able to creating indicators to twenty 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