The Correlator signal path begins with the arrival of the astronomical data on either tape or Mark 5 disk pack. The data analysts create jobs that read the information off the media and into the correlator. In the correlator, the data undergoes complex matrix multiplication, essentially multiplying the data from one antenna against all the other antennas synchronized by time.
Once the data are correlated, it is written to either a DAT (Digital Audio Tape) cassette, or loaded onto the server for FTP download by the observing astronomer at their home institution where they will process the data.
It is anticipated that by the end of 2006 that all astronomical data from the VLBA antennas will be recorded on Mark 5 disk packs. The tape drives will be left at several sites for an emergency backup recording system. The number of tape playback drives attached to the correltaor has been reduced to 9 from a maximum of 24.