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OPEN SHORT Calibration

Question asked by SOLT_guy on Feb 22, 2011
Latest reply on Feb 23, 2011 by SOLT_guy
Dear Sir:

       If you calibrate your network analyzer such that at 300KHz you achieve a perfect 180 degree phase difference between the open and short but at 1 GHz there is, let's say a -2 degree offset when you look at the open.

       Is this -2 degrees primarily the result of fringing capacitance (there may be tiny phase errors resulting from imperfect standards or imperfect characterization, let's assume those errors are small)?   Is the fringing capacitance the primary source of the phase shift under these circumstances? 

       Also, let's say you input fringing capacitance values in your cal kit but there physically exists a pin in your test set up causing fringing capacitance.   Will your network analyzer completely cancel out the fringing capacitance so that you don't see the -2 degree offset on the monitor after you input your fringing capacitance values, or due to the fact that your test set up has fringing capacitance at the open physically taking place in your experimental set up, the fringing capacitance will always be observed on your NA monitor?  

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