[wxsig] Wind direction calibration problem with WSI603

[Ted11]

I'm having some trouble calibrating the WSI603 (AAG RJ45 anemometer/vane
head).  The T238 screen says to point the vane to the north, which I do, and
then press select.  However, after I press select, the direction on the T238
display gives me a random direction, even though the vane is fixed and still
pointing to north.  Sometimes it's 225 degrees, sometimes 45, sometimes
another number.  I haven't seen a pattern.  After several recalibrations,
the device will eventually calibrate to north, but this seems to be just
luck.  Has anyone else run into this?  Connected to my laptop, I can
successfully calibrate the vane direction on the first try, so I think the
head is working properly.  

Thanks for any help. 

Ted
KE6ROS