Introduction
Antenna
Data Acquisition
Correlator
C-Rack
D-Rack
Mark 5 Disk Recorder
Tape Recorders
Maser
Station Computer
Communications
VLBA Array Operators
Data Acquisition signal path:
D-Rack
D-Rack. This rack contains three units: Baseband Converters that change the frequency of the astronomical signal; Samplers that take 'chunks' of data from the Baseband Converters at increments specified by the observing file (standard rate is 128 Megabytes per second); and the Formatter that converts the data from the Sampler for writing to media (tape or disk).
Data Acquisition signal path:
D-Rack


The D-rack contians three components of the signal path: the IF Distributor, the baseband converters (BBCs), and the formatter.

The IF Distributor distributes the four intermediate frequencies across the baseband converters.

The baseband converters select the specific frequency range that contains the astronomical data and extracts it from the 500 - 1000 MHz intermediate frequency.

The formatter takes the data from the baseband converter and formats it, along with the timing information from the C-rack, onto the recording media (tape or disk).