CAMAC Progress Report

                      Week Ending: April 26, 2002
                               Week: 65


Tom Folkers:
     1. Testing at HHT this week.
     2. I spend most of week sick. Not much use to anybody.

Tom Sargent:
     1. The new stop-in-path feature appears to be successful.  When 
        the telescope is following a sun avoidance path to slew to an 
        object, you can now change your mind by clicking on another 
        object (or a on several new objects in succession).  The 
        telescope comes to a stop while remaining on the sun avoidance 
        path, calculates a new path to the most recently selected 
        object and moves to it. 
     2. Beam switching (which didn't work on the last engineering run) 
        works well now. Plots of azimuth vs. time look pretty good. An 
        740 arcsec shift in Azimuth was done in times ranging from 2.8 
        sec. to 3.4 sec.
     3. Discovered and fixed a bug in the sun avoidance path 
        computation and in the code that monitors the difference 
        between the commanded and the observed velocities (stops the 
        telescope if the difference gets too large).
     4. Bill Peters and I compared the pointing accuracy of the old 
        system and the new system using the same pointing model. After 
        developing new fiducial cycle count values that make the 2 
        systems agree better, and checking precession (agreement is 
        very good). we are left with a difference in azimuth that runs 
        from about 2 arcsec at low elevation and about 12 or 14 arcsec 
        at high elevation. There's a smaller variation in elevation 
        which runs from 0 to 4 arcsec.  Since the old system is known 
        to be accurate to a small fraction of an arcsec, we must still 
        have some inaccuracy or omission in the new code.  We 
        collected some position vs. time data (which still needs to be 
        analyzed) which will allow us to verify the 2 systems' LST 
        values. A small systematic difference in apparent LST would 
        explain much of the problem.
     5. Worked more on the hide-from-sun code, but didn't get it far 
        enough to test it.

Pete Hubbard:
     1. SMT encoder testing with the lab amplifier chassis. First 
        looking at the signal coming from elevation motor encoder. The 
        60Hz was 102dB below the signal. I moved to elevation 1 
        encoder and the 60Hz was only 78dB below the signal. The 
        majority of the noise is between the SMT encoder and the 
        amplifier box on the wall. Further test and looking at cable 
        routing to find were the noise is being injected into the 
        cable.
     2. DBE mux chassis testing with the VCO signals looks good at the 
        differential receiver Am26LS32. The mux chip output had some 
        ground bounce but not enough to cause false triggering of the 
        counters.

Lori Warner:
     1. I was out sick three days this week.
     2. Continued learning GTK and GDK using your main.c example.I can 
        make several widgits, but now need to pack them in a box to 
        display on one screen. Getting into Drawing now.... slowly.

Dave Ashby:
     1. No Report.