There is no “free lunch” in transformer design. In ISO-MAX models with an “I” in the model number (CI-2RR and PI-2XX, for example), the Faraday shields responsible for extremely high noise rejection unavoidably makes their output sensitive to capacitive loading. Since the cable that connects isolator output to equipment input is the main source of capacitance, it must be kept reasonably short. Capacitance up to 200 pF, about 3 feet (1 meter) of standard cable, will preserve the rated high-frequency bandwidth. There is no restriction on length for the cable that connects equipment output to isolator input. Special-purpose isolators (PC-2XR and DB-2PX, for example) are more tolerant of longer cables.
Posted in: Iso-Max