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Дата изменения: Wed Mar 20 17:44:08 2002
Дата индексирования: Sat Dec 22 17:14:46 2007
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Cross Scan

This procedure uses the correlator to perform a cross scan on your chosen source. The only three options you have for this procedure is the number of loops (i.e. the number of complete cross scan patterns you wish to be performed), the cross scan pattern - either the `standard' cross ($+$) pattern which does one azimuth and one zenith scan, or a `spider' ( $+\!\!\!\!\!\times$) pattern which consists of four scans, each separated in position angle by 45$^\circ$, the starting offset of each scan (with the default set to be 3 times the half-power beam width of the telescope for that receiver). Data is currently sampled in this procedure every second, at a rate of 60 times per strip. This means that you MUST be careful not to over drive the telescope, a concern which is especially important for the lower frequencies and near zenith.