Agilent Technologies HP 8719D Service Manual page 451

where
Efnf = effective noise floor
n
Crtl = connector repeatability (transmission)
n
Crrl = connector repeatability (reflection)
n
Ctml = cable 1 transmission magnitude stability
n
Crml = cable 1 reflection magnitude stability
n
n
Dmsl = drift magnitudePC source to port 1
n
Efs = effective source match error
n
Efr = effective reflection tracking error
n
Efl = effective load match error
n
Efd = effective directivity error
n
n
The detailed equation for each of the previous terms is derived from the signal
flow model, located at the end of this appendix.
Reflection Phase Uncertainty (Erp)
Reflection phase uncertainty is determined from a comparison of the magnitude
uncertainty with the test signal magnitude. The worst case phase angle is
computed, This result is combined with the error terms related to thermal drift
of the total system, port 1 cable stability, and phase dynamic accuracy.
where
Cpfl = cable phase/frequency port 1
Dpsl = drift phase/degree source to port 1
Dpfsl = drift phase/degree/frequency source to port 1
+ 2Cpfl
x f + Dpsl + Dpfsl x f
Determining System Measurement Uncertainties A-5