VEGAS Team Meeting

June 04, 2012



  • Dan Werthheimer
  • Mark Wagner
  • Jayanth Chennamangalam
  • Glenn Jones
  • Mei Jun


  • Jason Ray
  • Marty Bloss
  • Anish Roshi
  • Ray Creager
  • John Ford
  • Galen Watts

Meeting Notes:

Next Teleconference: June 18. 2012

Observation Status:

No discoveries to report as analysis continues

VEGAS Mode Development Status:

Simon uploaded a code update to dump data to disk more often. This has been successfully tested in Berkeley, but it needs to be tested in GB. Maybe Ray and Anish can test this with the next round of VEGAS/GBT tests.

Work is focused primarily on Mode 13. Mei Jun has the filters working, and Jayanth is developing the new packetizer. The Roach2 board is up and running after a number of changes from 32-bit to 64-bit operations.

The new Roach2 layout is complete & reviewed and due for pre-production run to verify changes then a complete production of boards that will be provided to VEGAS.

The SFP+ is now working properly with some jumper wires; new layout is completed and ready to go into production

Testing Status:

The problem that banks don't start at correct time has yet to be resolved. Glenn and Ray will to collaborate to locate the problem and implement a solution.

GBT summer maintenance has now started so testing time (without GBT movement) will be easier to come by.

Galen reviewed the plota he uploaded at
  • Plot one shows the module with some adjustments
  • Plot two is after removing compensation and added 1st order positive slope to offset cable-induced negative slope.
  • After discussion the team agrees the performance in Plot one is actually preferable because a flat negative system slope is better than a flatter slope with irregular gain "bumps". The performance will be remeasured after the final ASIAA ADCs are in place.

Other items:

The test computer has been ordered with Green Bank as the delivery location.

-- MartyBloss - 2012-06-04
Topic revision: r1 - 2012-06-04, MartyBloss
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