CAMAC Progress Report

                    Week Ending: November 02, 2001
                               Week: 40


Tom Folkers:
     1. Spent week on site testing new servo system. Tom and Pete's 
        report sums it up best.

Tom Sargent:
     1. On Monday I prepared for the test run at the SMT. 
     2. The 3 Day observing run was moderately successful.  The 
        automated encoder-reset operation now works.  We discovered 
        that the Azimuth encoder has one reference pulse every 45 deg. 
        We chose the 90 deg. pulse as it looks the cleanest. All the 
        others have multiple minima.   There are still a couple 
        changes necessary, but the procedure works. 
     3. The new servo target acquisition software works better than 
        the previous (Sept.) version, but not as well as the old VAX 
        system's.  It still has too much over-shoot. We captured 
        position data for many different acquisition and beam 
        switching operations with different servo parameters and that 
        will be studied over the next couple of weeks. We also 
        captured position vs. time data for the old VAX system while 
        it was acquiring objects and beam switching.  We will use this 
        as the standard to decide how well the new servo software is 
        performing. 
     4. We discovered some noise sources at the SMT.  The 12-bit A/D 
        channels reading the coarse encoders show large amounts of 
        noise (0.2v) when the telescope is being driven, but not when 
        it is stationary. Filtering appears to be a practical 
        solution.  I also observed the Azimuth sine signal to show 
        large amounts (+-15%) of noise for a few minutes. The software 
        detected this through a couple of different monitoring 
        features.  It has been observed in the lab on other channels 
        twice before. We are still not sure of the source. It may be 
        thermal.
     5. The hand shake between the DSP and the Linux host needs to be 
        made a bit more defensive.  There were a couple of cases where 
        the DSP was not performing correctly and the servo program was 
        not aware of it. 

Pete Hubbard:
     1. Pack servo system for trip to SMT Oct 30,31 and Nov 1.
     2. Testing new servo system at SMT. This time looking at motor 
        currents and making a filter for coarse azimuth readout 
        signal. When moving the telescope the noise was 2 volts P-P 
        and after filtering it was reduced to 200 mv P-P.
     3. Unpacking and setting up new servo system in the lab.
     4. Starting to modify the third MPI 6000 Amp board to be used 
        with the new servo elevation encoder #2.

Dave Ashby:
     1. No Report.