Five emission arc lamps (Hg, Ar, He, Kr and Ne) and one continuum lamp are located inside the main housing of MX beneath the focal plane. These lamps provide calibration light to the fibers by reflecting off closed doors above the focal plane. These lamps may be turned on by any of three circuits. First, a set of manual toggle switches located directly on the ``D'Arc II Lamp Control Box'' located on the IIS -- the box was refurbished in 1995 by R. Ganguly and J. Hill. Second, a set of manual switches on the Enterprise Remote Box located in the control room. The Enterprise Remote Box also handles remote reset and collision override switches for the Enterprise as well as lamp control. Third, a set of computer commands sent through the CCD VxWorks computer from the ``ccdacq'' software. These computer signals travel via a serial current loop cable to the B&C Interface Box. Unlike the original version of MX lamp control, any of these three sources can turn on a lamp regardless of the state of the other two sources -- they are connected as a wire-OR. Any number of lamps may be turned on simultaneously.
To use the B&C Spectrograph lamp control for MX, set ``instrpars.instrname=bcspeclamps''. ``instrpars.complamp'' or ``comp.complamp'' determines which lamp or lamps will turn on. Leaving the ``complamp'' parameter blank turns all lamps off. Comparison lamps will only be turned on by the ``ccdacq.observe'' command when ``imagetype=comp'' (requiring a little trickery when using the MX lamps to take fiber flats or chip flats). You may turn the lamps on or off under computer control without taking an exposure by using the command ``instrument comp=lampname''.
To assist in taking fiber flat and top comparison arc lamps between MX integrations, we have written the script ``mxobserve.mxlamps.cl''. All you need to do is turn down the TV gain, close the barn doors, and type ``mxlamps'' -- assuming that you preset the parameters with ``epar''. Automation of the barn doors using the D'Arc lamp control box is described below.
cluster = Object title (nexpoz = 0) Number of zero exposures (exptiz = 0.) Exposure time, zeros (seconds) (zerotit= zero) Object title for zeros (nexpof = 1) Number of flat exposures (exptif = 15.) Exposure time, flats (seconds) (flatlam= mxcont0) Lamp for flats (flattit= fiber flat) Object title for flats (nexpoc = 1) Number of comp exposures (exptic = 80.) Exposure time, comps (seconds) (complam= mxar mxhe mxne) Lamp for comps (comptit= comp) Object title for comps (verbose= yes) (version= 21-OCT-95) Version date of script (mode = h)
B&C complamp Lamp CCD Bit ID J5 Pin# Designation Description Type ------ ------- ----------- ----------- ------ MX1 1 mxcont0 actual continuum lamp flat MX2 2 mxcont1 spare continuum lamp flat MX3 3 mxhg mercury lamp comp MX4 4 mxar argon lamp comp MX5 5 mxhe helium lamp comp MX6 6 mxkr krypton lamp comp MX7 7 mxne neon lamp comp MX8 8 mxsp (spare bit + buzzer) comp
Note that all the lamps in MX begin with ``mx'' to distiguish them from the normal lamps in the B&C Spectrograph with similar names (``quartz'', ``hear'', ``fene'').
As of July 1996, the new improved D'Arc lamp box has an automatic door closing circuit. With this feature enabled, the barn doors will automatically close whenever a lamp is turned on by the computer or manually. To enable the automatic door closing, set the Remote Box Doors Switch to ``closed'' and set the Autodoors Switch on the D'Arc Box to ``on''. For manual remote operation of the doors as before, set the Autodoors Switch to ``off''. Please turn the Autodoors Switch ``off'' at the end of the night to keep dust out of the instrument.
If Enterprise and the D'Arc lamp box are powered up while the B&C Lamp Controller is off, all the lamps will be turned on. To prevent the bulbs from burning out or something else from getting fried, we have installed a buzzer on the Enterprise remote box that beeps when this condition occurs. To stop the beeping, turn on the B&C Lamp Controller power supply above the CCD controller, or turn off the Enterprise power. (The buzzer really goes off anytime the non-existent #6 arc lamp -- ``mxsp'' -- is turned on.)
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