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<p>Thank you for the input.</p>
<p>Dave<br>
</p>
<div class="moz-cite-prefix">On 12/4/2024 4:39 PM, Emmanuel Momjian
via evlatests wrote:<br>
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<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif"></span><span style="font-size:11.0pt">Recently*, the S9 switches on the
output of the L301-2 in four antennas (ea02, ea08, ea14, and
ea17) were replaced with splitters. To evaluate if this
would have any impact on astronomical data, several RFI
sweeps were acquired.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">The
evaluation of the data, before and after the modifications,
as well as with and without the antennas in question, did
not show any noticeable issues in the spectra (e.g., no new
strong birdies due to the LO frequencies and/or their
harmonics).<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">It is worth
noting that of the tunings used in the RFI sweep, the only
time the L301-2 output frequency, or one of its first two
harmonics, falls within the recorded observing band is at
12160 MHz. This frequency does show a strong narrow-band
birdie, ~20 dB above the noise floor. However, this signal
was already present before the splitter modification and
does not appear to have changed significantly in strength
after the modification was done.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">If you
happen to see any new strong birdies in any of your recent
VLA data, please let us know asap.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Emmanuel and
Paul<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-ligatures:none">*ea08’s S9
switch was replaced with the splitter on or around Nov. 21,
2024. The work on the other three antennas was done on Nov.
25, 2024.<o:p></o:p></span></p>
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<br>
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