Testing March 11, 2014

KFPA observers (13B-312, RAMPS survey) had problems observing. Their configuration worked, but the data doesn't appear look right and we're getting some anonymously higher tsys. This is happening in multiple banks. Anish thinks it is a tuning problem.

Goal:

  • Figure out the problem with the KFPA configuration. We are inserting a test tone to see if things are turning correctly.

Session:

  • TGBT13B_502_43

Log:

  • Scan 46-47: Ran jfosterRAMPS script to see where test tone is.
  • Increased the power in Bank A.
  • Scan 48: Ran jfosterRAMPS script again to see where test tone is.
  • Scan 49: Ran jfosterRAMPS script again to see where the test tone is.
  • Scan 50: Ran jfosterRAMPS_VEGAS_BankA script to see where test tone is. Only using bank A. Tone appears to be in IF 4. test tone at 1.01 GHz.
  • Scan 51: Ran jfosterRAMPS_VEGAS_BankA script. turned tone off to see if signal in IF 4 disappears. it did.
  • Scan 52: Ran jfosterRAMPS_VEGAS_BankA script. turned on test tone to see if signal in IF 4 re-appears. it did (according to Anish). Because of the high power levels there are a lot of harmonics. input power -5 before. changed to -15. * Scan 53: Ran jfosterRAMPS_VEGAS_BankA script. * Changed input power to -20. * Scan 54: Ran jfosterRAMPS_VEGAS_BankA script. * Scan 56: Ran jfosterRAMPS_VEGAS_BankA script. Test tone only offset by 1.01 MHz not 6.2 MHz expected. * Scan 57: Ran jfosterRAMPS_VEGAS_BankA script. moved test tone by 6 MHz to 1.015 GHz. Output test tone only moved 3 MHz. * Shifted signal by 5 MHz. * Scan 58: Ran jfosterRAMPS_VEGAS_BankA script. Don't see a frequency shift. * Scan 59: Ran jfosterRAMPS_VEGAS_BankA script. Double-checking frequency shift. * Scan 60: Ran jfosterRAMPS_VEGAS_aakfreqs script. Putting in my observing frequencies to see if we see the test tone in this setup. * Scan 65: Ran jfosterRAMPS_VEGAS_aakfreqs script. 940 MHz, -5 dBm. Can see test tone at right frequency. * Scan 66: Ran jfosterRAMPS_vEGAS_aakfreqs script. Tone off. * Scan 67: Ran jfosterRAMPS_vEGAS_aakfreqs script. Moved test tone. * Scan 68: Ran jfosterRAMPS_VEGAS_rampfreqs script. Trying to see if we see the test tone for the observer's setup. No tone for this scan * Scan 69. Ran jfosterRAMPS_VEGAS_rampfreqs script. Turned test tone on: 200 MHz and -5 dBm. lowest IF frequency (0.20589GHz), which is highest spw frequency (24.53299 GHz). * Scan 70. Ran jfosterRAMPS_VEGAS_rampfreqs script. Trying to see what we see in highest IF frequency 1.2941 GHz (lowest frequency spw 23.44478 GHz). This is where the problem lies according to Anish. Turned test tone out: 1.25 GHz and -5 dBm. * Didn't see test tone. LO inside VEGAS doesn't appear to be working. Anish thinks that it should work up to 1 GHz. * remove splitter because sometimes blocks things above 1 GHz * Scan 71:Ran jfosterRAMPS_VEGAS_rampfreqs scripts. Turned test tone out: 1.25 GHz and -5 dBm. Getting rid of splitter doesn't fix problem. * Scan 72: Ran jfosterRAMPS_VEGAS_rampfreqs scripts. Test tone on: 1.040 GHz. WINDOW: 23.6947 GHz, IF freq is 1.0444 GHz. seeing test tone. Also seeing it in matching IF num 0 window. But this turning is greater than 1.0 GHz * Scan 73: Ran jfosterRAMPS_VEGAS_rampfreqs script. Test tone on: 1.2 GHz. IF freq: 1.2941 GHz Window 23.44478 GHz. Not seeing test tone. * Scan 74: Ran jfosterRAMPS_VEGAS_rampfreqs script. Test tone ON: 1.01 GHz. IF freq: 1.1062 GHz. Window 23.72265 GHz. Not seeing test tone. But Anish had wrong frequency setting. * Scan 75: Ran jfosterRAMPS_VEGAS_rampfreqs script. Test tone On: 1.01 GHz. IF freq: 1.1062 GHz. Window 23.72265 GHz. Saw test tone. * Scan 76: Ran jfosterRAMPS_VEGAS_rampfreqs script. Test Tone On: 1.2 GHz. IF freq: 1.2941 GHz Window 23.44478 GHz. Not seeing test tone, but that may be because something is tuned wrong. * Scan 77: Ran jfosterRAMPS_VEGAS_rampfreqs script. Test Tone On: 1.29 GHz. IF freq: 1.2941 GHz Window 23.44478 GHz. See test tone. So VEGAS appears to be okay. * Scan 78: Ran jfosterRAMPS_VEGAS_rampfreqs_allbeams. Checking IF paths and filters using IF manager. Noticed 950 MHz filter in VEGAS. Anish says that it shouldn't be there in the config. Maybe this is the problem. * Checked in dev explorer and checked filter manually and 1400 filter is selected. Looks like the above is an IF manager problem. * Scan 79: Ran jfosterRAMPS_VEGAS_rampfreqs_aakfreqs. Checking to see what band the doppler track frequency is in. Oops! This is an all bank A config. * Scan 80-81: Ran Mar03KFPAMode20OnOff7+2Beams8Spwsall. Checking to see what bank the doppler track freq is in. Bank E, same as other config, so that's not a problem. * Confirmed with spectrum analyzer that its a problem with how the manager is setting the filter.
Topic revision: r3 - 2015-01-27, RichardPrestage
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