MDM Trouble Report for 2009 Jun 14

Telescope: 2.4m
Observer(s): John Thorstensen (Dartmouth)
Instrument: Modspec + echelle CCD

Problem(s) Encountered:
The telescope stopped responding to east/west set and guide
commands issued from the paddle.  North/south was fine; the 
telescope had finished its set so it wasn't the hangup-on-set
problem.  Button pushes on the paddle did show up properly
on the lower-left corner of the TCS display -- so it was not a
bad connection to the paddle.  The telescope was tracking OK
and did respond to E/W offset commands from CCDCOM, so the 
motors weren't at fault.  To cure this, I turned the TCS computer
completely off using the procedure outlined in the lightning
shutdown, including the TCS power supply; for good measure
I cycled the power on the three motor-controller boxes in 
the left-hand computer rack.  The TCS came back fine (and
remembered the telescope position perfectly), and the problem
had disappeared.  

Also, at one point, when I was at an HA of -5 hr, the telescope
stopped tracking.  I was out of the room at the time and don't
have any context for this -- I just returned to find the 
autoguider beeping and the stars streaming across the field.  
I only lost a couple of minutes, and this didn't repeat, so 
probably no time should be wasted following it up; I'm just 
including it in case it starts becoming a pattern.

There was another AC power relay trip around dinnertime.  The
mirror had cooled all day so it wasn't too warm at the start.

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Submitted on 2009 Jun 15 [5:07:17]