ZPH Cable Rider 1-Port Cable & Antenna Analyzer 2MHz – 4GHz. – The R&S Cable Rider ZPH has all the essential basic measurement capabilities required for installing and maintaining antenna systems in the field. Its unique features ensure fast and efficient cable and antenna measurements and spectrum analysis. Two different R&S ZPH models are available to suit different needs, a pure one-port cable and antenna analyzer and a two-port model with additional spectrum analysis and tracking generator features.