[daip] FARAD question

[Hanno Spreeuw]

Hello, I have  a question about FARAD for WSRT data.
After changing the Stokes value from -5 to -1 in the header using PUTHEAD,
RL=Q+iU is now XY=-U+iV.
Assume V=0 for calibrators and target. XY=YX=real if the XY phase offset 
has been corrected for properly. Ionospheric Faraday rotation will then 
not affect the XY phase (~0), just the amplitude, if I am not mistaken.

Also XX and YY are affected because Q is affected by ionospheric Faraday 
rotation. For the VLA, RR and LL are not affected by ionospheric faraday 
rotation if I understand correctly.

Is it correct to infer that FARAD will not work for WSRT data because 
the XY phase does not change by ionospheric faraday rotation?
Is there a workaround? I mean, the RMs calculated by FARAD could still 
be used but would have to applied differently.

Hanno.