Here the raspi2 with the astrokit shield above.
This is the last proto =>
The imperfections and delay in the vertical motion of the video are due to gear lash on NEQ3-2 DEC
A long pose on EQ-MODE (about one hour) showing that system accuracy is better than EP from VIXEN GP (wich is about 30" arcsec)
The circle-shaped tracking is normal and due to the rotation of the DEC error vector,
due to the difference between the north pole-object circle radius and mount axis-object circle radius
you may notice than EP forms a periodic curve with 10 minutes period =>