TGBT14A _912_96-98 - Testing new BOF files for Modes 4-9, 10-19

Sessions 96 and 97

In Session 96, we tested the "Hardware Fix" for modes 10-19, which would allow us to use the proper BOF files. These tests failed, most easily seen by the fact that the shape of the bandpass was not constant from scan to scan. This is most easily seen in scans 8 and 9, ifnum=1, plnum=0 (see scanVariationMay14.pdf). We deem this fix is not ready for prime time.

In session 97, we tested the new BOFs for modes 4-9 without motion. All of the scans seem to show consistent structure between banks and scans. No major issues were found. The BOFs were used successfully for the receiver checkout (TSCAL_14MAY2015). Ron performed his non-linearity analysis on the RCO data, and found up to a 3 K difference in system temperatures when allowing for non-linearities.

Session 98

For the on sky testing, we looked at 4 flux calibration sources of varied strengths in S-Band. The center "dimple" was seen in all data.

  • Astrid Script : Linearity_Test_Sband_Mode_07 (Position Switched data (onoff))
    • Scan 13/14 - 3C123
    • Scan 15/16 - 3C147
    • Scan 17/18 - 3C147
    • Scan 19/20 - 3C147
    • Scan 21/22 - 3C147
    • Scan 23/24 - 3C227
    • Scan 25/26 - VirgoA

Ron performed his non-linearity test and found most of the data to be self-consistent, with surprisingly few signs of non-linearity (at least when performing quick checks). A 1-2% gain stability type effect was noted in 3C147 and VirgoA. This variation can be see in the standard gbtidl results after smoothing with a 100 bin boxcar.

  • Astrid Script : Linearity_Test_Sband_Mode_06 (Position Switched data (onoff))
    • Scan 27/28 - 3C147
    • Scan 29/30 - VirgoA

These data (mode 6) look a bit suspicious. There are some discontinuities in the spectra. Could it be RFI?

  • Astrid Script : Linearity_Test_Sband_Mode_09 (Position Switched data (onoff))
    • Scan 34/35 - 3C147
    • Scan 36/37 - VirgoA

  • Astrid Script : Linearity_Test_Sband_Mode_07_02 (Position Switched data (onoff) - stagger a few windows to see verify if RFI)
    • Scan 38/39 - 3C147
    • Scan 40/41 - VirgoA

The original Manager and BOFs have been replaced. Running a few tests to verify all is OK.

  • Astrid Script : Linearity_Test_Sband_Mode_07_02 (Position Switched data (onoff) - stagger a few windows to see verify if RFI - only look at VirgoA)
    • Scan 42/43

The new BOF file looks a whole lot better. Needs to be implemented quickly, but need to verify the high resolution 'edges' as shown below in red (which are not visible in the lower resolution mode):

high res shapes.png

  • Astrid Script : Linearity_Test_Sband_Mode_10 (Position Switched data (onoff) - stagger a few windows to see verify if RFI - only look at VirgoA)
    • Scan 44/45
    • Scan 46/47
All looks good. Leaving for the day. -- AdamKobelski - 2015-05-14
Topic attachments
I Attachment Action Size Date Who Comment
high_res_shapes.pngpng high_res_shapes.png manage 73 K 2015-05-18 - 09:29 AdamKobelski note the structure in red.
scanVariationMay14.pdfpdf scanVariationMay14.pdf manage 322 K 2015-05-14 - 18:11 AdamKobelski Scan Variation of the hardware fix from scan 8 to 9 with IFNUM=1 (bank C)
Topic revision: r3 - 2015-05-18, AdamKobelski
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