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Unlikely in this case. The signal appears to be about the same strength in all antennas, and we're in the A configuration — so an enormous range of distances from the cell tower. I would expect much worse behavior at the end of the east arm, but this is not
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<b>From:</b> evlatests <evlatests-bounces@listmgr.nrao.edu> on behalf of Paul Demorest via evlatests <evlatests@listmgr.nrao.edu><br>
<b>Sent:</b> Thursday, April 16, 2026 1:33 PM<br>
<b>To:</b> evlatests@listmgr.nrao.edu <evlatests@listmgr.nrao.edu><br>
<b>Subject:</b> Re: [evlatests] New (to me) L-band RFI</div>
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<div style="font-size: 11pt;">I've heard recent suggestion in RFI discussions that this freq range is now being handled by our favorite cell tower (T-Mobile @ gray hill) either instead of or in addition to SpaceX. Maybe someone with actual knowledge about
this could confirm/deny.<br>
<br>
If this is true, then this signal would not mitigated by ODS, but I would expect to see a noticeable antenna dependence with East-arm antennas more strongly affected (similar to what we see at 2150 MHz).<br>
<br>
-Paul<br>
<br>
________________________________________<br>
From: evlatests <evlatests-bounces@listmgr.nrao.edu> on behalf of Lorant Sjouwerman via evlatests <evlatests@listmgr.nrao.edu><br>
Sent: Thursday, April 16, 2026 12:46 PM<br>
To: evlatests@listmgr.nrao.edu<br>
Subject: Re: [evlatests] New (to me) L-band RFI<br>
<br>
Does ODS take into account the wide extent of the sidelobes or only the primary beam?<br>
<br>
<br>
On 4/16/26 11:33, Ylva Pihlstrom via evlatests wrote:<br>
Then indeed ODS should have been active and reporting to SpaceX.<br>
<br>
Ylva<br>
<br>
<br>
From: Rick Perley <rperley@nrao.edu><mailto:rperley@nrao.edu><br>
Date: Thursday, April 16, 2026 at 11:22<br>
To: Ylva Pihlstrom <ypihlstr@nrao.edu><mailto:ypihlstr@nrao.edu>, evlatests <evlatests@nrao.edu><mailto:evlatests@nrao.edu><br>
Subject: Re: New (to me) L-band RFI<br>
<br>
Ylva:<br>
<br>
The RFI was seen with the L-band receiver, in the 16th spectral window. The RIF wasn't strong enough to cause problems to any other SPW — and indeed, the portion of the 16th SPW lying outside that frequency range looked fine.<br>
<br>
Rick<br>
<br>
________________________________<br>
From: Ylva Pihlstrom <ypihlstr@nrao.edu><mailto:ypihlstr@nrao.edu><br>
Sent: Thursday, April 16, 2026 11:17 AM<br>
To: Rick Perley <rperley@nrao.edu><mailto:rperley@nrao.edu>; evlatests <evlatests@nrao.edu><mailto:evlatests@nrao.edu><br>
Subject: Re: New (to me) L-band RFI<br>
<br>
That band is exactly the one of SpaceX’s downlinks. If the L-band receiver was used, the ODS may or may not have been active depending on the frequencies used in the setup:
<a href="https://obs.vla.nrao.edu/ods/index.html/nrao_ods_status.html)" id="OWA34768b15-c07d-24f2-b0a7-943a8a187b11" class="OWAAutoLink" data-auth="NotApplicable">
https://obs.vla.nrao.edu/ods/index.html/nrao_ods_status.html)</a>.<br>
<br>
Ylva<br>
<br>
<br>
From: evlatests <evlatests-bounces@listmgr.nrao.edu><mailto:evlatests-bounces@listmgr.nrao.edu> on behalf of Rick Perley via evlatests <evlatests@listmgr.nrao.edu><mailto:evlatests@listmgr.nrao.edu><br>
Date: Thursday, April 16, 2026 at 11:11<br>
To: evlatests <evlatests@nrao.edu><mailto:evlatests@nrao.edu><br>
Subject: [evlatests] New (to me) L-band RFI<br>
<br>
>From data taken two nights ago, a strong RFI source at L-band is seen — on all antennas. It spans 1.990 to 1.995 GHz.<br>
<br>
Rick<br>
<br>
<br>
<br>
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<br>
<br>
--<br>
-<br>
<br>
Regards,<br>
<br>
Lorant Sjouwerman - Scientific Services - lsjouwerman@nrao.edu<mailto:lsjouwerman@nrao.edu><br>
(he, him, his) ----------------------------------------------<br>
c/o NRAO Array Operations Center Phone: +1-575-835-7332<br>
P.O. Box O (1011 Lopezville Rd) Switch: +1-575-835-7000<br>
Socorro NM 87801 Fax: +1-575-835-7027<br>
Also a PandA Adjunct Professor at the University of New Mexico<br>
<br>
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