What is the difference in accuracy when comparing the Instacal module with the precision calibration tee?
The InstaCal has a specified directivity of 38 dB for frequencies below 3.5 GHz while the regular calibration tee provides >42 dB of directivity. The directivity is many times the largest contributor to measurement uncertainty and this difference between the two calibration techniques will affect the uncertainty. The difference in performance will be more prevalent the closer to the directivity you are. For instance, if you are making a return loss measurement of an antenna and the overall system return loss is 10 dB, the difference in performance will be less than 0.1 dB. If the overall return loss is 20 dB, then the OSLN50-1 tee will be at least 0.35 dB better than the ICN50 Instacal. In general, it is recommended to use the InstaCal when you are looking for a fast way to make the cal. If superior accuracy is of important, then the precision calibration tee is the best way to go.