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OTHER DIGITAL BACKENDS:

There is a varient on the RDBE being developed at Haystack for mm VLBI that has 4 input IFs and does not attempt any filtration. It simply samples and formats the data and sends it to the recorders. It can put out 8 Gbps. This device is not yet supported by SCHED.

When the DAR is the RDBE, the output channels and all the input channel information given to SCHED are written to the VEX file. But the crd files that control the old VLBA hardware also has to be told something. SCHED does not have a separate set of variables for all those configuration parameters, so it just does something reasonable. It sets the number of channels to the maximum of the number requested and 8. It sets the frequencies to cover the middle of the RDBE basebands and the sidebands to match the RDBE basebands. It sets the sample rate to the maximum of that requested and 32 Ms/s. It sets the channel bandwidth to the lesser of the request and 16 MHz. It only writes the first 4 pcal extraction requests (avoiding going into channel numbers that are too high). Recording on the Mark5A system is not requested.


next up previous contents
Next: Spectral Line Observations Up: Wide Band Observing: RDBE, Previous: DBBC:   Contents
Craig Walker 2014-06-17