Most industrial installations for the reception of meteorological satellites use X-Y rotors. Choosing this type of rotor is not accidental. Medium speed in both axes, the absence of "dead zone" in the zenith and the problems associated to the crossing of the azimuth 0 degrees. This is a small list of advantages of this type of rotor.
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For construction, I used two mount PowerTech DG380 with metallic gear.
To obtain the angle 190 degrees is necessary to modify "STOP" switch.
Before 
and after modify 
You also need to flip the swith:
Before 
and after modify 
As the encoder use a resistor. In the future I plan to use AS5040 or AS5045.
Other parts X-Y mounts:
Finally, the assembled X-Y mounts and home-made 1.9m HRPT-antenna.
------------------------Add. Oct 2010-----------------------