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: http://www.atnf.csiro.au/people/Tasso.Tzioumis/sched/Setup_Files.html
Дата изменения: Unknown Дата индексирования: Sun Apr 10 08:43:27 2016 Кодировка: Поисковые слова: barnard 68 |
Setup files are used to provide station-specific input parameters. Most are for the VLBA, which requires complete configuration information be present in each VLBA control file, and the VLA, which requires information for the frequency setup. For each scan in a schedule, the setup file is specified with SETUP. Once specified, it need not be given again unless it changes. Several setup files may be used in a schedule -- usually for switching between frequency bands.
SCHED will not run without a setup file specified for each scan.
Setup files can be imbedded in the main program input, much like source and station catalogs. The group of inputs immediately before the setup file should contain the parameter SETINIT with an argument that gives this ``setup file'' (which may contain more than one group of stations) a name. This proceedure may be used multiple times to specify several ``setup files''. In the main schedule, the name given the imbedded file can be used as the argument to SETUP as if it were an external file.
The setup files can be used to control many aspects of the hardware setup at the stations. Mostly it is used to set frequencies and recording modes, but it also has pulse cal detection, pointing, and a number of other items. Most parameters can be left unspecified and SCHED, with the help of the frequency catalog, will find reasonable defaults. See the discussions of individual parameters for details. A reasonable minimum set would be: NCHAN, BBFILTER, BITS, POL (can be DUAL), and either BAND or FREQREF (and FREQOFF. Some users may wish to specify more information, for example BBC, NETSIDE, and FORMAT and perhaps many others rather than taking the defaults.
Each setup file can consist of several setup groups separated by ``/''. Each group applies to the stations listed. This allows some parameters, such as FIRSTLO, to be station specific. However, if no station specific values are included, stations may be lumped together into a single group even though SCHED will have to separate them before using other information to set the station dependent parameters. The ultimate case of this is to have just one setup group and not specify any stations. This is possible if only generic parameters are given. SCHED will figure out what stations are needed and establish the necessary setup information.
If you don't take the defaults, SCHED will check your setup against the information it has internally and in the frequency catalog. If your setup does not match one in the frequency catalog in terms of the setup of the IF's, SCHED will complain, but not stop. If the complaint is about a VLBA setup, you are probably using a poor set of synthesizer settings or have some other such problem because the frequency catalog contains an essentially complete list of reasonable setups. Please be aware that there are filters in the LO and IF signal paths of the VLBA that many users do not know about. If your setup is not in the frequency catalog, you may simply have specified the wrong IF or synthesizer or you may be trying to use a signal outside of the band of some filter. For other stations, the frequency catalog is not so complete. If SCHED complains, double check your parameters to be sure they are right. In such cases, it is best to email your setup to Craig Walker (cwalker@nrao.edu) for further checking.
If only generic parameters such as those above are specified, multiple stations can be specified for a setup group. SCHED will actually take those multiple stations and create multiple setup groups before filling in the defaults, many of which will be station dependent.