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The spectrometer software is written in Visual C++ and is Follow the Readme file instructions to properly load the software on your computer and review the computer hardware requirements.
From your chosen folder simply click SpectraCyber.exe. This will JSSatomicTime.exe which connects to the internet and updates your system clock to the nearest second, you could also create a shortcut for the desktop if you wanted an icon for it.
through the Control Panel, System, then Device Manager to:
Online and the product will query the SpectraCyber spectrometer.
Once two way communications has been verified then the main (Local Apparent Sidereal Time) depending upon the Time coordinate
selection described later. At the top are the are
several selections which open a separate dialog box. |
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to Windows. |
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Favorites - Load, Save, and Default:
user to save a favorite configuration for a target under study. One could save a favorite under a target name and then come back to it later. To pull up a previous favorite simply click on the Load menu item. If you want to have a standard default configuration you would save the current configuration to the filename: Default.fav, which is what the program loads on initialization.
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window, which may be useful for clean and clear Screen Prints or for the Plot Capture option which drops a .bmp file to be included in publication documents or an animated gif of the data. present data from the screen.
An X axis feature permits you to use either KHz or Km/sec on the axis.
The Km/sec is now based on the targets relative doppler shift velocity coordinates, and the frequency of the gas under study.
of the the gas/molecule you are imaging, which in turn affects the doppler shift velocity... As an example if you are working the Methanol 5th transition state at 6.667 GHz and downconverting this frequency to
1420.406 (Hydrogen) for the SpectraCyber then the doppler shift
For your reference, there is a
VSR JAVA calculator at the Jupiter
http://www.jupiterspacestation.org/software.html
Here you will find the Plot Zoom feature. Upon clicking this feature a dialog box comes up capturing the upper and lower Y-axis limits you wish to zoom too. The only restriction is that the lower limit cannot exceed the upper limit.
Another feature permits the user to use either dots or connected lines
or a bar for
the plotting. The Plotbar feature can only display in
The final feature is Plot Capturing. This feature permits the user to specify whether or not a bmp graph file is created on each save of the scan. This does not drop a bmp for each AutoSave during the scanning process; the user must load the scans they like, re-save them, and the bmp is created if the Plot Capture feature is on...
The user can also ran a single scan and save it to produce the bmp. A 13k bmp can be converted to a 6 k gif file with almost any
graphic software package.
The Plot Capture also now lets you select just a plot or the whole
screen
the plot on your screen.
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Data which has been stored on disk can be played back in a
When you left click Pick Starting File bar a dialog box will guide you asking for the path and file prefix name to play. The files to play should have been previously stored on the hard disk by the Autosave command (described later). The filename prefix could be something like C:\YourDir\Data\Orion.1 The C: represents your hard disk or perhaps a floppy disk drive. The name of the files to display is Orion. After clicking select Pick Ending File to specify an ending file extension in the data series. The file extension is the suffix after the period in a
The Autosave command will automatically increment this data movie. After entering a number for the start press
Tab
After entering the ending # press TAB. Next you will be asked for a delay. This represents the delay in seconds or fractions of seconds to pause between each screen of data. A short delay of .2 seconds runs the movie quickly while a long delay of 1 second per frame moves more slowly. This allows close examination of small changes in the graphs. Just enter the desired delay in seconds and press TAB.
You will then select Single or Continuous play of the movie. In single play the movie runs once and then returns to the command state, in continuous play the movie is automatically started over at it's end. Simply enter S or C followed by a clicking on OK. The movie should start and display the file name and the date it was recorded at the upper portion of the screen.
To start the movie click
On... To stop the movie click Off.
moving average for your plots and you can then choose how effect of further smoothing your plots.
And finally Inverse: this has the
effect of mirror image flipping |
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Scan: kill a movie which is in progress. Plotting will indicate when a scan is in progress and will cease when scanning is stopped.
A Scan Rate feature permits you to speed up the scans by a factor of up to 4x. Basically this changes the between point scans from either 5 or 10 KHz (depending on your upper/lower limits) to as much as 4x or 20 - 40 KHz.
A selection of Rescan On or Rescan Off toggles the screen rescan on or
Autosave On or Autosave Off
clicked automatically saves plots of data when Target name is used for the filename and the data is stored in the Data folder. This path
helps to better organize things as it is a good idea to use which would save on the C: drive in the DATA subdirectory. As an example: ORION.1 THRU ORION.999
The path and file prefix will be shown in the plot area
Load and Save feature bars permit individual scans to be loaded for viewing or stored for later analysis.
Next comes a powerful operations feature: Que. The software has the ability to start data collection at a point which is chosen in the future. When the Que bar is left clicked you will get a dialog box which prompts you to enter the countdown time until data collection. An example could be 15 hours 21 minutes. After entering this time press TAB and you will be asked for the lapse time to run the observation using the spectrometer data collection. The times must be in 24 hour format. Click OK when done. The data would be stored under the Target name as the Autosave saves the file. As an example it could be C:\YourDir\Data\Orion. This will save files named Orion.* on drive C in the DATA subdirectory. If you wish to abort this Que operation, simply click Que Off.
There are two powerful features at work here: first, a Que.fav file is saved to be retrieved when the countdown kicks the job on, and second, the user can use the spectrometer and software during the countdown
period. |
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By clicking Online a dialog box of settings comes up for you to initialize the spectrometer settings. When completed with filling out the settings values the spectrometer moves to Online if the communications channel is open. In Offline mode the spectrometer can be completely exercised using a dummy Sagittarius data set.
The backend unit is equipped with a relay to supply +12vdc the relay on or off. This command may be used during the scan acquisition to record a reference power level.
Time System... the user may select either a UTC or LAST (Local Apparent Sidereal Time) time coordinate system for data file stamps. Each time LAST is selected the user may enter the local latitude and longitude coordinates which will become the default for all sessions thereafter; also one would note that the current Julian Day is also displayed in this dialog box. Some users like LAST displayed so that they can easily estimate when the target
comes up on their
local meridian.
integrate for each plot point.
This would be especially useful for
The last option is the Input Frequency Shift. This brings up a dialog box which wants to know how much (in KHz) you want to shift the the x axis values. If you have equipment that can position a range of frequencies (like 1416 to 1428 MHz) onto a center IF frequency of 70 MHz (which is one of the input frequencies of the SpectraCyber), then you can have this frequency shift reflected on the x axis. This permits you to investigate velocities greater than 2 MHz in a given direction and have the velocities properly reflected on the x axis.
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The backend unit is a dual channel spectrometer and
(optinally) a continuum will change the selected mode. The choices are
Spec Mode which is spectrometer windows... too be implemented later). The spectrometer channel is in the main window and the continuum channel is in the same window (if selected). In Both mode the continuum channel is used as a check to see if there have been any signal level fluctuations while the spectral scan has been in progress by having both active in two different windows. Dual mode has the disadvantage of consuming twice the disk space for each screen of data.
Integration acts like a capacitor charging up with signal and then is tapped at intervals specified by Time/step (DT). Standard integration values for Spectral mode are .3, .5, and 1.0 seconds; Continuum mode are .3, 1.0, and 10 seconds.
A few units have the option of either 15 or 30 KHz IF bandwidth. The default is 15 KHz.
Target permits the user to set a target/filename for data and for the title line on the plot... If the user does not specify anything then the words SPEC or CONT are used along with date stamping to indicate target information.
Gain and Offset require a special operation detailed as follows. These two control functions.. DC Gain and DC Offset are duplicated twice... once for the spectrometer channel and once for the continuum channel. To make a change to any of these values click on the appropriate menu bar item on the top of the window.
DC offset adjustments are for the spec and continuum channels and requires is left clicked the user
may enter a dc offset level from 0 to 5 vdc. The
The Scan or Sweep limits are used to set the upper and lower scan limits This corresponds to blue shifted doppler signals. Enter a value from 0
Keep in mind that the spectrometer moves in 5/10 Khz steps so these values should be integer multiples of 5/10. An entry such as 183 Khz would be invalid, however 185 would be fine. The program selects -600 and +600 for the limits at start up (unless you modified them in your favorite
file). Most signals observable with a smaller dish will be in this
A final note about the x axis values: depending on your upper and lower limits there are 4 possible ranges: -2000 to 2000 (10 KHz steps), -1000 to 1000 (5 Khz steps), 0 to -2000 (5 KHz steps), and 0 to 2000 (5 KHz steps). Above we described a Scan Rate feature which speeds up scanning by jumping steps 2x to 4x.
The Time/Step or DT bar allows a change in the "Delta Time" or simply the time between sample data points. In
Spec mode this is usually 1 If you enter 0 seconds it will be "rounded up " to .2 seconds.
Above 1 second values are rounded to the nearest whole second. Continuum only mode stores 360 data points per screen while Spec mode has 400 data points per screen.
Finally Rest Frequency Correction permits the user to tune the spectrometer so that the hydrogen rest frequency will be precisely 0 MHz on the Doppler x axis scale. Typically the units come from the factory with a precise
clocking of the hydrogen frequency. |
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The Port selection permits the user to designate COM1 or COM2 as the computer port interface to the spectrometer.
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This Web selection permits the user to go onto the internet to set the computer clock to within 1 second of NIST time, go to the support site to pick up new releases of SpectraCyber and the documentation, or jump to the SpectraCyber sales site for information on new radio astronomy equipment.
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This Web selection permits the user to select software or hardware help on this product as well review the Readme file for installation instructions. Information about the Development Team can be found in the Help About SpectraCyber selection.
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