1. LCAT1000-09 Substitution Conclusion The LCAT1000-09 is identical to the original part FMAT7620-9 in terms of attenuation value, power handling, impedance, and connector interface. Therefore, it can serve as a direct drop-in replacement for frequencies up to 6 GHz, with no issues in electrical performance or mechanical compatibility. The key difference lies in the frequency range: the original part covers DC to 18 GHz, whereas the LCAT1000-09 is limited to DC to 6 GHz. If your application circuit or test system operates above 6 GHz (for example, in Ku‑band applications from 12 to 18 GHz), using the LCAT1000-09 will result in severe performance degradation. This includes significant deviation from the nominal attenuation, degraded VSWR, and the introduction of unacceptable signal distortion and measurement errors. Conversely, if the application is strictly confined to frequencies below 6 GHz (such as most mobile communications and Wi‑Fi bands), the LCAT1000-09 is a qualified substitute. The feasibility of substitution depends entirely on whether your maximum operating frequency exceeds 6 GHz.