24jun21 calOn/Off sun, no hub amps.



   Debugging the xband hub amps (20db)  showed that they were causing a problem. on 23jun24 they were brought down to the lab for testing. The xband chain was left connected with a bullet rather than the amps. This reduced the gain in the chain by 20db and increased Tsys by about 40 K (more info).

    Cal on,offs were then repeated on and off the sun, as well as a few driven scans across the sun. This was to see whether the system was still saturating while on the sun. This would give us an idea of how large an attenuator we'd need when looking at the sun.

    The cal on off setup was:

Processing the data

Plotting the calOn,off results:

    The plots show the results of the calon,offs (.ps) (.pdf):

Scanning across the sun

Processing the data:

    The azimuth offset was computed using the azimuth position in the header and the azimuth value coming from the ephemeris file (that tracked the center of the sun);.   

Plotting the strips    

The plots show 3 scans across the sun (.ps) (.pdf)


processing: x101/210624/onoffsun.pro,scansun.pro

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