Betsy, Jeff and I did a measurement of the maximum obtainable pitch and yaw range on the rebuilt Quad #2 using an optical lever. According to Norna's write up, T1000268-v1 ( https://dcc.ligo.org/cgi-bin/private/DocDB/ShowDocument?docid=11868 ) we should be able to get 1.4 mrad in each direction at the optic. At the DOF Test screen we applied successively offsets of +2556 and -2556 in pitch and +7863 and -7863 in yaw, which with the usual output matrix maxes out (32K) at least one of the OSEMs. The resulting deflections of the optical lever spot were +9.5 and -11.5 cm in vertical (+=down) and +5.5 and -6.5 cm in yaw (+=left). The optical lever baseline was 4.98 m. 

This implies a total range of 1 mrad in pitch and 0.5 mrad in yaw, which is rather less than expected. A big chunk of this is that the actual UK driver boxes for the test stand were not built to the 200 mA max output assumed in T1000268. To check this, the voltage across the face1 coil was measured at the simulated vacuum flange, with 32K-1 of offset applied at the Output Filters screen. The resistance (including that of the cables) was 39.9 ohms and the voltage was 3.69 V implying a maximum current of 92.5 mA.

The fact that the pitch range is larger than the yaw is probably connected with the fact that the fundamental pitch mode frequency is rather lower than in the model, i.e., there is more pitch compliance than expected.