With network-analyser you can measure only up to 6 GHz. For higher frequencies you have to use generator and power-meter. This article describes how does the author measure such relays available from various manufacturer such as Narda
Tree different kind of SMA-relay were measured till now: one from 1P2T from Narda and Radiall and one 1P6T from RLC. Next pictures show attenuation of Narda SEM020 relays, two pieces (S/N 5782 and S/N 2037) were measured. Every picture contains a black and a red graph. The black plot is what was measured with the power head connected to the generator without the relay (all other adaptors were still in between). This plot is used as a reference. There are some ups and downs in the curves due to resonances. I did not figure out where the resonances came from, high grade adaptors were used. The red plot shows the measured attenuation thru the relay. The both straight lines are the linear fittings of the curves, the black line is the fitted reference, the red line is the fitted attenuation curve.
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