TGBT19A_502_04,05 - VEGAS LBW Pulsar Modes Release


  • Release new M&C version to support VEGAS LBW pulsar modes and some new HBW BOF files
  • Test BTL configuration, C-Band RRL set-up, and Argus as a sanity check


  • Joe completed software switch at 12:45.
  • We did a quick check by configuring for coherent pulsar, then multi-bank spectral line mode. This worked. Joe found a legit bug in config tool that was causing the issues last time.
  • Ray joined us at 13:00 and will release some of his patches.
  • All patches are in place at 13:30.
  • Ran the KEYSTONE_L11_OnOff_Test script to check KFPA configuration.
    • Got a balance error from VEGAS even though all power levels look OK. Astrid says that CM attenuators 6 and 7 need further adjustment.
    • This seems to be a legitimate issue with wildly varying power levels on the second inputs of Banks B and C. Both of these are coming in through optical receiver 4.
      • We talked to Galen and this is due to a problem with the laser diode on this optical driver. We are going to put this in dev health and see if we can route around it for Bank C and D.
      • This does not impact the incoherent modes unless people try to use multiple VEGAS banks and one of them is Bank B or C. It also does not impact the coherent modes, because they use the Bank C and D HPCs but don't route any IF paths through the relevant OD.
  • We were able to run some BTL scans using the OREO interface. Things seemed to run properly but the BTL manager was not getting the correct sky frequency. Ron says this happened yesterday as well. Ray determined that BTL gets this information from the IF manager. It does not seem like this should be related to the new VEGAS branch.
  • C-Band RRL setup seemed to work OK
  • We had to take Beam 12 out for the Argus setup due to the OD4 issue, but it ran OK after that.
  • The KEYSTONE setup failed when configuring after the Argus scan. Astrid says that it cannot route 122 paths to VEGAS.
    • Running a ResetConfig before before configuring for KFPA solves this
    • Verified that this happens when going from Argus to KFPA w/out a ResetConfig
    • We switched to the old version of ConfigTool to see if it happened on the old branch
      • The same error happened on the old ConfigTool branch. This would seem to be a bug in existing config tool, and so not something we need to delay the release over.
  • Everything looks good so far. Will do some on-sky tests after the receiver checkout.
  • Starting motion tests at 18:00. Weather is partly cloudy.
  • Did peak focus scans at X-Band. They seem OK other than some baseline structure and the Tsys is 29 K.
  • Going to do an RRL observation of W43G based off of AGBT18B_014 at C-Band
    • Scheduling block does calibration scans on 3C48 first.
    • First it is doing peak and focus scans. Tsys is about 26 K
    • It seems as if this source is not currently up. Grrr. Doing S209 instead from the same scheduling block. Not seeing obvious data to compare to, but maybe I can find something later.
      • It does seem like this project will run tonight, so I can check it out then.
    • I don't have baseline data to compare to on hand, but I do see lines at the center of the band in most IFs, and the scan ran without issue. I think this probably looks fine, just fine.
    • Going to switch to Argus now.
      • Ran Dave's vancal idl program. Most beams have Tsys around 215-220 K. Some are a bit lower. Beam 2 is extremely high with Tsys of almost 3000, so something is wrong there. Beam 3 is somewhat higher than the rest at 247 K, but I think this is somewhat expected.
      • Also ran Dave's argus_onoff idl script. I see two very nice narrow lines at about 88.61 and 89.18 GHz, both with Ta* of around 10 K (baseline is about 1 K). I think this is probably pretty good.
    • Going to test a KFPA setup from KEYSTONE/GAS. The sources I originally planned on are not up now (did I get the times confused before the first release attempt??) but I am going to try a 30-second track on L1489PPC, and part of a map on MonR1. I'm not sure what L1489PCC actually is, so there may be no lines to speak of, but we'll see. Note that beams 4 and 5 will not be used because OD4 is out of service. These correspond to VEGAS Banks C and D.
      • I see some NH3 lines in ifnums 7 and 8 of fdnum 0. They are at 23.694 GHz. It is there in both polarizations with a Ta of about 4 K peak.
      • I think this is probably sufficient as a checkout. Not going to do the map of MonR1.
  • I am pretty happy with things here. I am going to use the remaining time to check out the i0100x8192 scheduling block.
    • Levels are on the high side but bandpass seems OK.
    • For some reason, Bank E is taking data. Bank A might be as well. This is similar to what happened during the receiver checkout.
      • I talked to Joe and looked at past receiver checkouts. This seems to be normal behavior.
    • Not seeing the pulsar, though.
    • Adjusted levels and tried again. Still no pulsar. Going to try a tone injection.
      • There are a lot of birdies but I think that I do see the tone.
    • Trying this again with the boom out.
    • Saw the pulsar this time but there was still a slight frequency shift, or at least there is a DM sweep in the fold-mode data.
    • The pulsar wasn't seen in the i0100x1024 mode either. Oh, I know why. The boom wasn't out. Dum dum dum dum dum.


  • All checks looked OK. We are staying on this branch.
-- RyanLynch - 2019-05-15
Topic revision: r3 - 2019-05-15, RyanLynch
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