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<p>Hi Rick,</p>
<p><br>
</p>
<p>It looks like our main dipole culprit is ea01. The dipole itself
is not orthogonal (elements twisted) and we are going to have to
get with the mechanics to get it removed so we can align it or
install the spare.</p>
<p><br>
</p>
<p>ea11 (on the other hand) looks to be aligned well (if you wanted
to use it as a reference).</p>
<p><br>
</p>
<p>Rob<br>
</p>
<p><br>
</p>
<p><br>
</p>
<div class="moz-cite-prefix">On 9/10/2024 3:43 PM, Rick Perley via
evlatests wrote:<br>
</div>
<blockquote type="cite" cite="mid:MN6PR14MB71472397D118DFA0FBCAB96BD79A2@MN6PR14MB7147.namprd14.prod.outlook.com">
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<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Ther results of a polarization calibration of a recent P-band
dataset (obtained via VLITE) indicate a significant number of
antennas with apparently misaligned feeds. </div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
As this was a VLITE database, there were only 18 antennas
included, one of which was out of service. For the seventeen
others, the calibration shows seven antennas misaligned by more
than 5 degrees w.r.t. the reference dipole (ea01). They are:</div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
ea17 5.7 degrees</div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
ea07 8.6</div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
ea11 10.3</div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
ea20 5.7</div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
ea23 5.2</div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
ea27 8.0</div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
ea21 8.6</div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
It is my impression (but I do not have the data in hand to prove
it) that this is worse than what was seen a few years ago. </div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
These misorientations should be easily visible from the antenna
surface. It would be good to know if visual inspection agrees
with the observations. </div>
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<br>
</div>
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Rick</div>
<br>
<fieldset class="moz-mime-attachment-header"></fieldset>
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</blockquote>
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