The VLA array of 27 antennas is configured in the four configurations namely A,B,C & D. The maximum antenna separation for these configuration are given in the table 3.1. Sometimes hybrid configurations such as 'DnC' and 'BnA' are configured in which the antennas on the east and west arms are moved in for the next configurations, but those on the north arm remain extended for a short time to enhance the view of the sources in the southern sky near the Galactic center.