J. Kissel, H. Radkins

To investigate the H1 EX GND T240's input matrix confusion, I drove down to the end-station to check the alignment of the T240. I've found the "N" label pointing in the North direction, which for LHO is the +X direction. Seems logical. 

However, looking further into the T240's user's manual, on pg 23, section 5.2, table 5-1 (for revision 6; in revision 4 has this table on pg 14, section 4.4, table 4-1) it states 

Axis    Orientation        Positive Voltage
 X       east-west         represents motion to the east
 Y       north-south       represents motion to the north
 Z       vertical          represents upward case motion

Hence, the "N" label should be aligned parallel to the Y axis, and it is not. 

We've misplaced all of our alignment rods (STS2s and T240s alike), so Hugh's ordering some stock to make several "swizzle sticks" which have ends that fit in both instruments (see SEI aLOG 523 for dimensions of the alignment holes). Once we have an alignment rod, I'll rotate the T240 and correct the input matrix.

The attached pictures show proof of the mis-alignment:
Page 1: From a distance, looking EAST (-Y direction), with the WEST wall at my back, and BSC4 to the left; the T240 sits in its black igloo at the focal point of the picture.
Page 2: A little closer now, igloo removed, looking in the same direction (EAST, -Y).
Page 3: Even closer, but now I've rotated to look DOWN, SOUTH (-Z,-X) direction, with the +X direction and BSC4 at my back.
Page 4: And ... scene. Looking in the SOUTH / -X direction I see the "N" staring me in the face. Eureka!