MDM Trouble Report for 2004 Mar 29

Telescope: 1.3m
Observer(s): armstrong, farber (columbia)
Instrument: echelle

Problem(s) Encountered:
Trouble getting counts at start of evening; missed flats. 
Problem corrected itself by the time it was dark enough to get
star data.

First 90-minute run went fine.

About 30 minutes into the second run, every few images were
badly contaminated by horizontal streaks.  Looked to be symptoms
of an electronics problem.

For an example, look in: tambora/data/eve/n01/v393hya
ccd.350.fits.

We were at airmass ~ 2.2.  Slewed to zenith, took 20 more 
images.  Same problem.

Switched off/on the ccd (in dome) 3 times; did a  df echelle  each
time ... finally got communication back the 3rd time.

But for about 20 minutes after that,  ut  read:
 +40 V at +172.7           CCD temp at +653.1   (Temp diode reads 645)
 +15 V at -20.8       CCD set temp at +826.8     Elapsed time   33.600
 -15 V at +72.4   Electronics temp at +5216.2   Requested time    1.040
  +5 V at +112.04       Heater voltage    4%       Heater rate  0x54e1


Decided to try an exposure anyway.  Had been disabling the ccd 
wipe, and thought the problem could be a result of charge buildup.
So enabled the wipe.  Images looked fine.

10 minutes later, ut reading was also normal.  Everything went 
smoothly for the rest of the night.

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Submitted on 2004 Mar 30 [4:12:10]