lwa-project / lwa_sv

The Advanced Digital Processor at LWA Sevilleta
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"Jump" in spectra after applying equalizer coefficients #19

Open jaycedowell opened 1 year ago

jaycedowell commented 1 year ago

Something is happening to the observations of @cdilullo that is causing a "jump" in the spectra at/near the adp3/adp4 boundary.

jaycedowell commented 1 year ago

This seems to also be happening with the lightning data now that we have #22.

jaycedowell commented 8 months ago

I'm also seeing this in some recent data I was taking for an interferometry test. We'll see if https://github.com/lwa-project/lwa_sv/commit/81996d92c569038036cdab3c473ab758d6777691 helps. That clips the coefficient values at ~[0.8229, 1.7178] which corresponds to about the frequencies where @cdilullo is (still) seeing jumps in his data.

jaycedowell commented 8 months ago

Still there at ~78 MHz. Maybe I need to clip farther down?

jaycedowell commented 8 months ago

Interesting. That last set of coefficients still doesn't remove the jump at 78 MHz.

jaycedowell commented 8 months ago

https://github.com/lwa-project/lwa_sv/commit/e9e53d583051e2fe6768fe0140a8762de1896e4d - Another attempt clipping at 73.5 MHz.

jaycedowell commented 8 months ago

Seems better, a little bit of a slope there about 78 MHz.

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