The forthcoming release of the control software for the LA19-13-04B 8.5 GHz VNA will include the option for TRL/TRM calibrations. This is a powerful addition to the capability of the already versatile instrument. It is a particularly useful tool for accurately evaluating high frequency SMT devices on printed circuit boards. The feature includes a facility for correcting errors arising from deviations in the impedance of the reference line used to carry out the calibration. An Application Note describing the techniques can be downloaded here. V1.21 of the software is due for release in July 2021.