Problem(s) Encountered:

Tracking in both axes was bad. Intermittent chiming from or behind the TCS

computer in the control room, science images visibly drifting on a timescale of a few minutes. The  Camera Control  window in MaximDL intermittently displayed the error message  “Failure to activate guide relay”  (not in time with the chimes), at random intervals roughly every few seconds on average.

Solutions:

Stop tracking.  In MaximDL,  Camera Control  -->  Guide  tab.  Click the  Settings  button in the middle to open the  Guider Settings  window.  Guider Settings  -->  Settings  tab.  In the  Autoguider Output  box (middle-right), next to the  COM Port  click the  Setup  button.  This displays info about the guider scope. DO NOT CHANGE ANYTHING. Just click  OK. Click  OK  to close the Guider Settings window.  Now start tracking again: Do the Guide --> Expose to check guider coords, and then start tracking.