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First VLBI using the Mark 5 VLBI Terminal 2003/11/24


The radio telescope at Hartebeesthoek spends a substantial amount of time operating as part of various global networks or radio telescopes, using the technique known as Very Long Baseline Interferometry (VLBI).

In this type of observing, the radio signals from distant objects in space are recorded and later shipped to a central correlator computer for processing. Until now, only magnetic tape provided sufficient bandwidth to record these signals. However, computer disk technology has now reached the point where the signals can be recorded on disk packs.

This technology has been built into the Mark 5 VLBI recording system, developed at Haystack Observatory in the USA and now coming into use around the world. This permits data recording at 1 Gigabit per second for 24 hours.

HartRAO's Mark 5A terminal arrived in 2003 October. Large numbers of disks were bought and integrated on site into disk packs for this system. The first VLBI using this terminal was run on November 24.

The images below show stages in the construction of the packs of disks for the terminal.

first disk
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Piet Louw is seen above installing the first disk drive into a pack.

gently does it
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Pieter Stronkhorst demonstrates the recommended method of gently ensuring that all the disk drives fit correctly in the chassis.

checking a disk pack
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Jonathan Quick checks the assembly of a disk pack. For some reason he thought it had been hit with a hard, blunt object.

installing a disk pack
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Jonathan installs a disk pack in the Mark V terminal for the first VLBI.