MDM Trouble Report for 2001 Sep 10

Telescope: 1.3m
Observer(s): Kemp (Columbia)
Instrument: Templeton/direct

Problem(s) Encountered:
Early in the evening, the manual set/guide telescope directional control
keypad in the control room began to intermittently fail.  It would often
go in one direction and then not move in the opposite direction.  Several
repeated attempts would usually eventually result in movement in the
desired direction.  This problem appeared only in the north-south axis.
Later, I found this to be true when moving the telescope at guide speed on
the console out in the dome.  These failures were noted each time to be an
inability to move to the south.

In the last hours of the night, the guiding program (working with the
transplanted 2.4m guider) twice failed to keep the star at the specified
position.  When observing several hours west of the meridian at +63
degrees, the telescope drifted south, failing to make northerly
corrections as the guide star appeared to drift out of the north side of
the guide box;  when observing several hours east of the meridian at +63
(different object later in the morning), the telescope drifted north,   
failing to make southerly corrections as the guide star appeared to drift
out of the south side of the guide box.  Each time, I would try to restart
the guider program, but often ended up rebooting the guider PC and/or
restarting the control console in the dome, hoping that one or both would
help resolve the problem.

This failure mode appears to be intermittent.  Each guiding failure was
followed by a period of successful guiding.  This problem might appear to
be a problem in the drive relays out in dome.

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Submitted on 2001 Sep 10 [5:46:40]