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<p>Hi Vivek,</p>
<p>The tests I ran on ea22 show that the sub-reflector has to be
moving (focus or rotation) to cause the RFI. I don't know the
exact nature or frequency of the RFI on ea22 yet.</p>
<p>Rob<br>
</p>
<div class="moz-cite-prefix">On 3/25/2021 1:58 PM, Vivek Dhawan via
evlatests wrote:<br>
</div>
<blockquote type="cite"
cite="mid:082e5633-2b2b-c139-90cf-7847c17bb74f@nrao.edu">Hi guys,
<br>
<br>
I can take a look at L band today after test/maint is
<br>
done. will let you know. Does FRM need to be moving for
<br>
the purported signal to be seen or we just don't know yet.
<br>
<br>
We did a recent sweep for checking if the operator's
<br>
webcam made any RFI. I attach a plot from mar 11, pink=
<br>
webcam on, green = off,unplugged. the 1830 is about 1.5-2MHz
<br>
wide. stuff at 1785 is a mystery.
<br>
<br>
<br>
On 3/25/21 1:39 PM, Rob Long via evlatests wrote:
<br>
<blockquote type="cite">Could this possibly be related to the
L-band issue we have on ea22? We know there is a huge
interference from the FRM drive on ea22. I don't think servo has
been able to investigate yet.
<br>
<br>
Rob
<br>
<br>
On 3/25/2021 1:00 PM, rperley via evlatests wrote:
<br>
<blockquote type="cite">In some recent observing at L-band, an
ubiquitous RFI spike was seen. It is:
<br>
<br>
- at 1830.0 MHz
<br>
- is seen on most, if not all antennas
<br>
- was present in every one of the 14 databases I have, all of
which were taken at night
<br>
- seems to be spectrally unresolved
<br>
<br>
It looks like an internal (or nearby) birdie.
<br>
<br>
Can anybody suggest an origin?
<br>
<br>
Rick
<br>
<br>
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