Dear listmembers,

I am wondering if any of you who have experience with Kiel devices have seen the
problem we have been having with ours.  On a irregular basis, the Kiel falsely
determines that it is on position 1 when in fact it is between positions.  For
example, after reacting a sample in position 4, the Kiel takes down the vial and
proceeds to position 1.  Somewhere between position 4 and position 1, the Kiel
stops between adjacent positions.  This could be between positions 4 and 5 or
anywhere.  Extensive observation and testing has revealed that it can occur when
"go to the position 1" command is issued in standby mode, during a sequence
acquisition or as the result of a manual keyboard input.  The problem is
intermittent-sometimes it will fail repeatedly, other times it will function
flawlessly for hours.  No other position is falsely read-only position 1, and
the carousel always moves at least half a position before it thinks it is on
position 1.  It has never failed to recognize the true position 1 as such.  I
have not been able to correlate its behavior with anything thus far.    I have
cleaned the encoder disk, shielded it from ambient light, adjusted the position
of the photo coupler array, tested the signals generated by the photo
couplers-all to no avail.  The couplers appear to work correctly and the other
tests and adjustments have made no difference.

Any and all suggestions, comments, wild hunches, etc., would be greatly
apprecitated.

Reed McEwan
Stable Isotope Lab
University of Minnesota
612 624 3348