Presumably. I would measure with a Q meter or a calibrated capacitor and a FET probe and a 'scope or Valve Voltmeter. Any analyser that relies on measuring return loss has a problem with measuring with any real accuracy impedances (or reactances) far away from 50 ohms. For example, the difference in return loss between 2500 ohms and 2400 ohms is around 0.1 dB. Which is why, although these modern analysers are quick and easy to use, I still prefer my old GR and Wayne Kerr RF bridges.