6.12 Formatter

The formatter selects the desired bit streams from the samplers, adds time tags, and supports various other functions that were required to record effectively on the VLBA's original tape-based data acquisition system. Although no longer required for disk-based recording, these functions are still operational in the transitional Mark 5A system described in Section 6.13. Auxiliary detection of up to 16 pulse-calibration tones and state counts also is supported in the formatter. This subsection will become obsolete when the new digital backends and Mark 5C recorders are installed on the VLBA later in 2010. See the beginning of Section 6 for further information.