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<p>Hi Rick,</p>
<p><br>
</p>
<p>I actually think it has a poor performing receiver. We've run
plots that look normal and plots that look weak. We're planning to
swap the receiver and check all connections while we are there.</p>
<p><br>
</p>
<p>Rob<br>
</p>
<p><br>
</p>
<div class="moz-cite-prefix">On 11/18/2024 4:43 PM, Rick Perley via
evlatests wrote:<br>
</div>
<blockquote type="cite" cite="mid:DM4PR14MB71327EE71755786A6EE5D2A0D7272@DM4PR14MB7132.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);">
I wrote earlier noting that the power gain of ea21 in the
Vertical polarization was low by a factor of about ten. </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 isn't always like this. Over the past two nights, we've had
9 short (40 minute) observations of a strong calibrator. For
all antennas except ea21V, the gains are wonderfully stable, and
nearly the same between all antennas. Just what we like to
see. </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);">
For ea21, the 'H' polarization is like the other antennas. But
the 'V' polarization is very different:</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);">
For 6 of the 9 observations, the correlated power is about a
factor of ten low. For the other three observations, it's close
to the other antennas. But, for one of these, the antenna gain
changed from a 'good' state to the 'bad' state steadily over an
~8-minute duration. </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>
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Very strange behavior. </div>
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<br>
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Sadly, ea21 is on pad E72, making it hard to get to ...</div>
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<br>
</div>
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Does anybody have an idea of what is wrong here? </div>
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<br>
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Rick<br>
<br>
</div>
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