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<p class="MsoNormal"><span style="font-size:11.0pt">Thanks for sharing, Rick. Spectrum Management is hoping to stand up a JIRA-based RFI reporting tool (internal use, all sites) that will be ideal for reports like this. Stay tuned!<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"><b><span style="font-size:12.0pt;color:black">From:
</span></b><span style="font-size:12.0pt;color:black">evlatests <evlatests-bounces@listmgr.nrao.edu> on behalf of Rick Perley via evlatests <evlatests@listmgr.nrao.edu><br>
<b>Date: </b>Monday, January 22, 2024 at 12:15 PM<br>
<b>To: </b>evlatests@listmgr.nrao.edu <evlatests@listmgr.nrao.edu><br>
<b>Subject: </b>[evlatests] Persistent P-band RFI<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">There are two 64-MHz-wide bands within P-band that are relatively free
<br>
of RFI, and are still useful for science: 288 -- 352 MHz, and 388 -- <br>
444 MHz.<br>
<br>
However, within that upper band, there is a persistent, everpresent, and <br>
very strong source of RFI which requires a good chuck of frequency space <br>
to be removed. I attach a .png file to show its characteristics -- this <br>
is a ten-minute long observation of the calibrator 3C48. These data <br>
were taken Saturday afternoon. The entire 8-hour run was affected about <br>
equally -- it never goes away.<br>
<br>
The isolated vertical bar on the left is at 403.50 MHz. The other major <br>
ones that are visible are at 407.25, 408.0, 409.5, and (weaker on tdhe <br>
right) 411.75 MHz. There is plenty of evidence for pulsed emission, but <br>
the strongest stuff looks very constant in time.<br>
<br>
Is there any chance this is local? And if so, can we turn if off?<br>
<br>
Rick<o:p></o:p></span></p>
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