L1LBW1 Testing

Mode 4

  • 32k channels
  • chan_bw 3433 Hz
  • center_frequency 750.0MHz
  • tone ~701 MHz
  • I would predict the tone to be in 2111, I see it in 1238 (or something else very prominent).
  • Something is there, but nearly as strong as Mode 5:
  • Data file: 2013_12_30_16:17:19H.fits
Tone in channel 2111 ?

Mode 5

  • 65k channels
  • chan_bw 2861 Hz
  • center_frequency 750.0MHz
  • tone ~701 MHz
  • I would predict the tone to be in 15641
  • Data file: 2013_12_30_15:39:20H.fits
Tone in channel 15641

Mode 6

  • 131072 channels
  • chan_bw 1430.5 Hz
  • center_frequency 750.0MHz
  • tone ~701 MHz
  • I would predict the tone to be in 31283
  • Data file: 2013_12_30_16:31:52H.fits

Tone in channel 31283

Modes 7-9

Not enough bandwidth to see the 701MHz tone.

Mode 10 (L8LBW1)

  • 32k channels
  • chan_bw 715.25 Hz
  • center_frequency 700.01 MHz
  • tone ~701 MHz
  • I expect the tone in channel 17782, looks like its in 19147. Nothing at all at 17782.
  • Something like a 980 KHz difference.
  • Data file: 2013_12_30_16:56:02H.fits

Mode 23 (L8LBW8)

  • 32k channels
  • chan_bw 715.25 Hz
  • center_frequency 700.01 MHz (subband 0)
  • tone ~701 MHz
  • I expect the tone in channel 17782, looks like its in 19148. Nothing at all at 17782.
  • Something like a 980 KHz difference.
  • Data file: 2013_12_30_17:13:27H.fits

Mode 2

As a sanity check, try checking the tone using mode 2 as a reference.
  • 16k channels
  • chan_bw 91553 Hz
  • center frequency 750 MHz
  • tone ~701 MHz
  • I expect the tone to be in channel 7657. There it is right on 7657.

I can't explain the reason for l8 mode oddness, even including the 'actual' LO frequency, the feature isn't landing where I expect it to. I also don't know why Mode 4 didn't show the line stronger, as it is usually relatively strong.

-- JoeBrandt - 2013-12-30
Topic revision: r1 - 2013-12-30, JoeBrandt
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