Bottom elliptical SUM Meter reads close to zero on Multimode. (0.1?)

celliott posted on Fri, Sep 30 2011 9:04 AM

rated by 0 users

We have a nice Multimode NSIV that we haven't used at all for the last couple of years (just busy with other research).  I tried to start it up today and it all looks good, but I can't get any kind of SUM on the bottom elliptical meter (after I've aligned the laser to cantilever using paper method and placed the tip holder in the microscope, etc.)  I don't remember this ever happening before.  I've adjusted the mirror tilt and photodetector knobs and still get nothing in the elliptical SUM.  I get values that change in the bottom display (vert/hor difference) and top display (tapping mode or contact output signal) but the elliptical SUM meter says at approx. 0.1.