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CX2SA > SATDIG 19.10.19 19:49l 932 Lines 26991 Bytes #999 (0) @ WW
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Sent: 190926/1346Z @:CX2SA.SAL.URY.SOAM #:14858 [Salto] FBB7.00e $:AMSATBB14361
From: CX2SA@CX2SA.SAL.URY.SOAM
To : SATDIG@WW
Today's Topics:
1. ARISS Contact Colorado University/Northridge Elementary
School Successful (US#454) (Bob)
2. ARISS Contact Colorado University/Northridge Elementary
School Successful (US#454) (Bob)
3. Tweet from AMSAT (@?????? (JoAnne K9JKM)
4. Re: Satellite mode announcement (Burns Fisher)
5. Re: Satellite mode announcement (Paul Stoetzer)
6. Re: Satellite mode announcement (JoAnne K9JKM)
7. Re: Satellite mode announcement (Graham Shirville)
8. Upcoming ARISS Contact Schedule as of 2019-09-25 02:00 UTC
(aj9n@???.????
9. AO-92 L/v mode switch (Ronald G. Parsons)
10. Re: AO-92 L/v mode switch (Rick Tejera)
11. Re: RHP LHP (Hasan al-Basri)
----------------------------------------------------------------------
Message: 1
Date: Tue, 24 Sep 2019 14:15:27 -0400
From: Bob <WB4SON@?????.???>
To: AMSAT-BB <AMSAT-BB@?????.???>
Subject: [amsat-bb] ARISS Contact Colorado University/Northridge
Elementary School Successful (US#454)
Message-ID:
<CAPonRZ-VrJtVv1CnryRH9rRyGRma==CejFOOBbvWzJqu-gbENQ@????.?????.???>
Content-Type: text/plain; charset="UTF-8"
Just a quick update to let everyone know that the contact today between
Astronaut Nick Hague and Northridge Elementary School (Colorado University
in Boulder) was a complete success. All 16 student questions were asked
and answered. One of the teacher questions was asked and answered before
Claudio IK6SLD, who's team did a fantastic job at the ground station,
completed the contact. My thanks for Charlie AJ9N who moderated the
contact.
Colorado University Aerospace, The Boulder Amateur Radio Club (BARC), and
the University of Colorado Amateur Radio Club hosted the event and did a
wonderful job.
The contact began at 17:43 UTC and ended at 17:55 UTC on September 24, 2019
73, Bob, WB4SON
ARISS Mentor
------------------------------
Message: 2
Date: Tue, 24 Sep 2019 14:16:42 -0400
From: Bob <WB4SON@?????.???>
To: AMSAT-BB <amsat-bb@?????.???>
Subject: [amsat-bb] ARISS Contact Colorado University/Northridge
Elementary School Successful (US#454)
Message-ID:
<CAPonRZ9uJvYUZ=QaRKfpHNEAY9ZYwbCWBQh2NW3MYNo76zdLyw@????.?????.???>
Content-Type: text/plain; charset="UTF-8"
Just a quick update to let everyone know that the contact today between
Astronaut Nick Hague and Northridge Elementary School (Colorado University
in Boulder) was a complete success. All 16 student questions were asked
and answered. One of the teacher questions was asked and answered before
Claudio IK6SLD, who's team did a fantastic job at the ground station,
completed the contact. My thanks for Charlie AJ9N who moderated the
contact.
Colorado University Aerospace, The Boulder Amateur Radio Club (BARC), and
the University of Colorado Amateur Radio Club hosted the event and did a
wonderful job.
The contact began at 17:43 UTC and ended at 17:55 UTC on September 24, 2019
73, Bob, WB4SON
ARISS Mentor
------------------------------
Message: 3
Date: Tue, 24 Sep 2019 14:52:10 -0500
From: JoAnne K9JKM <joanne.k9jkm@?????.???>
To: AmsatBB <amsat-bb@?????.???>
Subject: [amsat-bb] Tweet from AMSAT (@??????
Message-ID:
<CANOtx_fBs=uP9O9boONXYt8gqhRij1tXmr8Q4H0erzUz96+ZuA@????.?????.???>
Content-Type: text/plain; charset="UTF-8"
Seen on Twitter first. Relay to the -bb.
AMSAT (@?????? tweeted at 0:56 PM on Tue, Sep 24, 2019:
An update on LauncherOne's progress. The second flight of LauncherOne will
carry RadFxSat-2 / Fox-1E to orbit.
(https://twitter.com/AMSAT/status/1176555939786362880?s=09)
Get the official Twitter app at https://twitter.com/download?s=13
------------------------------
Message: 4
Date: Tue, 24 Sep 2019 16:29:43 -0400
From: Burns Fisher <wb1fj-bb@??????.??>
To: Zach Metzinger <zmetzing@?????.???>
Cc: AMSAT BB <amsat-bb@?????.???>
Subject: Re: [amsat-bb] Satellite mode announcement
Message-ID:
<CABX7KxV0mz=oVLhGmhJ9pVJLB4kdJRYB0Q8Nrk==cSY=Fx-Vqg@????.?????.???>
Content-Type: text/plain; charset="UTF-8"
Ooh. Maybe even better would be text like those messages AMSAT-UK puts on
AO-73.
On Mon, Sep 23, 2019 at 11:40 AM Zach Metzinger via AMSAT-BB <
amsat-bb@?????.???> wrote:
> On 2019-09-23 08:15, JoAnne K9JKM via AMSAT-BB wrote:
> > You'll still be able to see AMSAT's latest tweet even if you don't have a
> > Twitter account:
>
> It'd be even cooler if future satellite firmware announced the upcoming
> schedule and/or active mode in CW (or PSK31, etc.) on the beacon frequency.
>
> Seems like a waste to have an orbiting bulletin-board-like-system which
> is immune to Internet outages and not use it...
>
> --- Zach
> N0ZGO
> _______________________________________________
> Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available
> to all interested persons worldwide without requiring membership. Opinions
> expressed
> are solely those of the author, and do not reflect the official views of
> AMSAT-NA.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
>
------------------------------
Message: 5
Date: Tue, 24 Sep 2019 16:35:42 -0400
From: Paul Stoetzer <n8hm@????.???>
To: Burns Fisher <wb1fj-bb@??????.??>
Cc: AMSAT BB <amsat-bb@?????.???>
Subject: Re: [amsat-bb] Satellite mode announcement
Message-ID:
<CABzOSOoRd4EzBdwJ3sJQ9Xy4xGPQ+2JuDTknZwB1g=XuuhV5=Q@????.?????.???>
Content-Type: text/plain; charset="UTF-8"
I think we should go old school and put CODESTORE on our next satellites.
Throwback to AO-6 and AO-7. Those who can copy the CW can get the
announcements :)
73,
Paul, N8HM
On Tue, Sep 24, 2019 at 16:31 Burns Fisher via AMSAT-BB <amsat-bb@?????.???>
wrote:
> Ooh. Maybe even better would be text like those messages AMSAT-UK puts on
> AO-73.
>
> On Mon, Sep 23, 2019 at 11:40 AM Zach Metzinger via AMSAT-BB <
> amsat-bb@?????.???> wrote:
>
> > On 2019-09-23 08:15, JoAnne K9JKM via AMSAT-BB wrote:
> > > You'll still be able to see AMSAT's latest tweet even if you don't
> have a
> > > Twitter account:
> >
> > It'd be even cooler if future satellite firmware announced the upcoming
> > schedule and/or active mode in CW (or PSK31, etc.) on the beacon
> frequency.
> >
> > Seems like a waste to have an orbiting bulletin-board-like-system which
> > is immune to Internet outages and not use it...
> >
> > --- Zach
> > N0ZGO
> > _______________________________________________
> > Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available
> > to all interested persons worldwide without requiring membership.
> Opinions
> > expressed
> > are solely those of the author, and do not reflect the official views of
> > AMSAT-NA.
> > Not an AMSAT-NA member? Join now to support the amateur satellite
> program!
> > Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
> >
> _______________________________________________
> Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available
> to all interested persons worldwide without requiring membership. Opinions
> expressed
> are solely those of the author, and do not reflect the official views of
> AMSAT-NA.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
>
------------------------------
Message: 6
Date: Tue, 24 Sep 2019 15:43:16 -0500
From: "JoAnne K9JKM" <joanne.k9jkm@?????.???>
To: "'AMSAT-BB'" <amsat-bb@?????.???>
Subject: Re: [amsat-bb] Satellite mode announcement
Message-ID: <5d8a7fe3.1c69fb81.67289.93b1@??.??????.???>
Content-Type: text/plain; charset="us-ascii"
> Ooh. Maybe even better would be text like those messages AMSAT-UK puts on
> AO-73.
What's cool is I can capture the telemetry and the "Fitter" text messages in
real-time for AO-73, EO-88, and JO-97. You need to read Arabic for EO-88.
--
73 de JoAnne K9JKM
k9jkm@?????.???
------------------------------
Message: 7
Date: Tue, 24 Sep 2019 22:28:36 +0100
From: Graham Shirville <graham@?????????.???>
To: JoAnne K9JKM <joanne.k9jkm@?????.???>, 'AMSAT-BB'
<amsat-bb@?????.???>
Subject: Re: [amsat-bb] Satellite mode announcement
Message-ID: <a6b57a3c-274d-58ba-a559-272f79f6c36c@?????????.???>
Content-Type: text/plain; charset=utf-8; format=flowed
Simply email operations@???????.???.??? to request FITTER messages to be
uploaded - please keep them short and give us a couple of weeks notice
if you can...As well as being available for download on 2 metres they
can be also be seen via the internet here
http://data.amsat-uk.org/ui/fc1-fm/fitter
73
Graham G3VZV
On 24/09/2019 21:43, JoAnne K9JKM via AMSAT-BB wrote:
>> Ooh. Maybe even better would be text like those messages AMSAT-UK puts on
>> AO-73.
> What's cool is I can capture the telemetry and the "Fitter" text messages in
> real-time for AO-73, EO-88, and JO-97. You need to read Arabic for EO-88.
>
> --
> 73 de JoAnne K9JKM
> k9jkm@?????.???
>
>
> _______________________________________________
> Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available
> to all interested persons worldwide without requiring membership. Opinions
expressed
> are solely those of the author, and do not reflect the official views of
AMSAT-NA.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 8
Date: Wed, 25 Sep 2019 01:29:32 +0000 (UTC)
From: aj9n@???.???
To: amsat-bb@?????.???
Subject: [amsat-bb] Upcoming ARISS Contact Schedule as of 2019-09-25
02:00 UTC
Message-ID: <1323029852.8361445.1569374972438@????.?????.???>
Content-Type: text/plain; charset=UTF-8
Upcoming ARISS Contact Schedule as of 2019-09-25 02:00 UTC
?
Quick list of scheduled contacts and events:
?
About Gagarin From Space, Meeting of 30 universities, Plovdiv, Bulgaria,
direct via? LZ1KDP
The ISS callsign is presently scheduled to be RS?ISS
The scheduled astronaut is Aleksey Ovchinin
Contact was successful: Tue 2019-09-24 16:10 UTC (***)
?
University of Colorado Amateur Radio Club and Northridge Elementary School,
Boulder, CO, telebridge via IK1SLD
The ISS callsign is presently scheduled to be OR4ISS
The scheduled astronaut is Nick Hague KG5TMV
Contact was successful: Tue 2019-09-24 17:43:20 UTC 86 deg (***)
Watch for livestream starting about 15 minutes before AOS at
http://www.ariotti.com
?
UAE school #1 with Space Flight participant, direct via TBD
The ISS callsign is presently scheduled to be RS?ISS
The scheduled astronaut is Hazza Al Mansour
Contact is go for Fri 2019-09-27 12:10 UTC ?
?
Kursk, Russia, direct via TBD
The ISS callsign is presently scheduled to be RS?ISS
The scheduled astronaut is Aleksey Ovchinin
Contact is go for Fri 2019-09-27 15:25 UTC
?
UAE school #2 with Space Flight participant, direct via TBD
The ISS callsign is presently scheduled to be RS?ISS
The scheduled astronaut is Hazza Al Mansour
Contact is go for Sat 2019-09-28 11:20 UTC ?
?
Amur State University, Blagoveshchensk, Russia, direct via TBD
The ISS callsign is presently scheduled to be RS?ISS
The scheduled astronaut is Aleksey Ovchinin
Contact is go for Sat 2019-09-28 14:35 UTC
?
Sonoma County Main Library, Santa Rosa, CA, telebridge via K6DUE
The ISS callsign is presently scheduled to be NA1SS
The scheduled astronaut is Nick Hague KG5TMV
Contact is go for: Tue 2019-10-01 19:53:13 UTC 82 deg
?
UAE school #3 with Space Flight participant, direct via TBD
The ISS callsign is presently scheduled to be RS?ISS
The scheduled astronaut is Hazza Al Mansour
Contact is go for Wed 2019-10-02 09:45 UTC
?
?
?
AMSAT-UK International Space Colloquium
Sat 2019-10-12 to Sun 2019-10-13
?
?
The ARISS webpage is at http://www.ariss.org/ ???
Note that there are links to other ARISS websites from this site.
?
The main page for Applying to Host a Scheduled Contact may be found at
http://www.ariss.org/apply-to-host-an-ariss-contact.html ???
ARISS Contact Applications (United States)
?
?
For many years I have on purpose not given the actual hyperlinks; I assume
the user would do a copy/paste into their favorite browser.? I am now
thinking that the browsers have all grown up and most should be able to
handle the link.? Please let me know you experience any issues.? So now you
should be able to directly click on the link.? (***)
?
Note, all times are approximate. ?It is recommended that you do your own
orbital prediction?or start listening about 10 minutes before the listed
time.
All dates and times listed follow International Standard ISO 8601 date and
time format YYYY-MM-DD HH:MM:SS
?
The complete schedule page has been updated as of?2019-09-25 02:00 UTC.? (***)
Here you will find a listing of all scheduled?school contacts, and
questions, other ISS related websites, IRLP and Echolink websites, and
instructions for any contact that may be streamed live.
?
http://www.amsat.org/amsat/ariss/news/arissnews.rtf
http://www.amsat.org/amsat/ariss/news/arissnews.txt
?
?
The successful school list has been updated as of 2019-09-25 02:00 UTC. (***)
http://www.amsat.org/amsat/ariss/news/Successful_ARISS_schools.rtf
?
?
?
The ARISS webpage is at http://www.ariss.org/ ???
Note that there are links to other ARISS websites from this site.
?
The main page for Applying to Host a Scheduled Contact may be found at
http://www.ariss.org/apply-to-host-an-ariss-contact.html ???
?
ARISS Contact Applications (United States)
?
The ARISS webpage is at http://www.ariss.org/ ???
Note that there are links to other ARISS websites from this site.
?
******************************************************************************
******************************************************************************
****************
ARISS Contact Applications (Europe, Africa and the Middle East)
?
Schools and Youth organizations in Europe, Africa and the Middle East
interested in setting up an ARISS radio contact with an astronaut on board
the International Space Station are invited to submit an application from
September to October and from February to April.
Please refer to details and the application form at
www.ariss-eu.org/school-contacts.? Applications should be addressed by email
to:? school.selection.manager@????????.???
?
ARISS Contact Applications (Canada, Central and South America, Asia and
Australia and Russia)
?
Organizations outside the United States can apply for an ARISS contact by
filling out an application.? Please direct questions to the appropriate
regional representative listed below. If your country is not specifically
listed, send your questions to the nearest ARISS Region listed. If you are
unsure which address to use, please send your question to the ARISS-Canada
representative; they will forward your question to the appropriate
coordinator.
?
For the application, go to:? http://www.ariss.org/ariss-application.html.
ARISS-Canada and the Americas, except USA: Steve McFarlane, VE3TBD email to:
ve3tbd@?????.???
ARISS-Japan, Asia, Pacific and Australia: Satoshi Yasuda, 7M3TJZ email to:
ariss@???????.???? Japan Amateur Radio League (JARL) http://www.jarl.org/
ARISS-Russia: Soyuz Radioljubitelei Rossii (SRR) https://srr.ru/
?
?
******************************************************************************
ARISS is always glad to receive listener reports for the above contacts.?
ARISS thanks everyone in advance for their assistance. ?Feel free to send
your reports to aj9n@?????.??? or aj9n@???.???.
?
Listen for the ISS on the downlink of 145.8? MHz.
?
******************************************************************************
*
?
All ARISS contacts are made via the Kenwood radio unless otherwise noted.
?
******************************************************************************
*
Several of you have sent me emails asking about the RAC ARISS website and
not being able to get in. ?That has now been changed to http://www.ariss.org/
?
Note that there are links to other ARISS websites from this site.
?
****************************************************************************
Looking for something new to do?? How about receiving DATV from the ISS??
Please note that the HamTV system has been brought back to earth for
troubleshooting.? Please monitor ARISS-EU or ARISS-ON for the very latest
news on the troubleshooting efforts.?
?
If interested, then please go to the ARISS-EU website for complete details.?
Look for the buttons indicating Ham Video.????????????
?
http://www.ariss-eu.org/
?
If you need some assistance, ARISS mentor Kerry N6IZW, might be able to
provide some insight.? Contact Kerry at kbanke@?????????.???
?
?
The HamTV webpage:? https://www.amsat-on.be/hamtv-summary/
?
?
****************************************************************************
ARISS congratulations the following mentors who have now mentored over 100
schools:
?
Satoshi 7M3TJZ with 136
Francesco IK?WGF with 132
Gaston ON4WF with 123
Sergey RV3DR with 121 (***)
?
****************************************************************************
The webpages listed below were all reviewed for accuracy. Out of date
webpages were removed, and new ones have been added.? If there are additional
ARISS websites I need to know about, please let me know.
?
?
?
Total number of ARISS ISS to earth school events is 1334. (***)
Each school counts as 1 event.
Total number of ARISS ISS to earth school contacts is 1277. (***)
Each contact may have multiple schools sharing the same time slot.
Total number of ARISS supported terrestrial contacts is 47.
?
A complete year by year breakdown of the contacts may be found in the
file.
http://www.amsat.org/amsat/ariss/news/arissnews.rtf
?
Please feel free to contact me if more detailed statistics are needed.
?
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
The following US states and entities have never had an ARISS contact:
South Dakota, Wyoming, American?Samoa, Guam, Northern Marianas Islands, and
the Virgin Islands.
?
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
?
QSL information may be found at:
http://www.ariss.org/qsl-cards.html
?
ISS callsigns: DP?ISS, IR?ISS, NA1SS, OR4ISS, RS?ISS
?
****************************************************************************
Frequency chart for packet, voice, and crossband repeater modes showing
Doppler correction? as of 2005-07-29 04:00 UTC
http://www.amsat.org/amsat/ariss/news/ISS_frequencies_and_Doppler_correction.r
tf
Check out the Zoho reports of the ARISS contacts
?
https://reports.zoho.com/ZDBDataSheetView.cc?DBID=412218000000020415
****************************************************************************
?
Exp. 59 on orbit
Christina Koch
Aleksey Ovchinin
Nick Hague KG5TMV
?
Exp. 60 on orbit
Luca Parmitano KF5KDP
Alexander Skvortsov
Drew Morgan KI5AAA
?
****************************************************************************
73,
Charlie?Sufana AJ9N
One of the ARISS operation team mentors
?
------------------------------
Message: 9
Date: Tue, 24 Sep 2019 21:28:30 -0500
From: "Ronald G. Parsons" <w5rkn@?????.???>
To: "AMSAT-BB" <AMSAT-BB@?????.???>
Subject: [amsat-bb] AO-92 L/v mode switch
Message-ID: <69999AABEC0C453C85F3CCE28213A972@?????????>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
In case anyone missed it. N8MH just tweeted:
Mark Hammond
@????
AO-92 in mode L/v at 0205 z for 24 hours. 9-25-19. New schedule for the next
few months!
Ron W5RKN
------------------------------
Message: 10
Date: Tue, 24 Sep 2019 21:03:00 -0700
From: "Rick Tejera" <SaguaroAstro@???.???>
To: "'Ronald G. Parsons'" <w5rkn@?????.???>
Cc: 'AMSAT' <amsat-bb@?????.???>
Subject: Re: [amsat-bb] AO-92 L/v mode switch
Message-ID: <00ca01d57356$22025ea0$66071be0$@???.???>
Content-Type: text/plain; charset="us-ascii"
I'm going to give the 011UT pass from DM33 a go. Keep an ear our for K7TEJ
Rick Tejera (K7TEJ)
Saguaro Astronomy Club
www.saguaroastro.org
Thunderbird Amateur Radio Club
www.W7TBC.org
-----Original Message-----
From: AMSAT-BB <amsat-bb-bounces@?????.???> On Behalf Of Ronald G. Parsons
via AMSAT-BB
Sent: Tuesday, September 24, 2019 7:29 PM
To: AMSAT-BB <AMSAT-BB@?????.???>
Subject: [amsat-bb] AO-92 L/v mode switch
In case anyone missed it. N8MH just tweeted:
Mark Hammond
@????
AO-92 in mode L/v at 0205 z for 24 hours. 9-25-19. New schedule for the next
few months!
Ron W5RKN
_______________________________________________
Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available to all
interested persons worldwide without requiring membership. Opinions
expressed are solely those of the author, and do not reflect the official
views of AMSAT-NA.
Not an AMSAT-NA member? Join now to support the amateur satellite program!
Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 11
Date: Thu, 26 Sep 2019 08:36:05 -0500
From: Hasan al-Basri <hbasri.schiers6@?????.???>
To: Jean Marc Momple <jean.marc.momple@?????.???>
Cc: "amsat-bb@?????.???? <amsat-bb@?????.???>, RG
<marzo7088@?????.???>
Subject: Re: [amsat-bb] RHP LHP
Message-ID:
<CAM4UQf0i4=jZ5uQrisyQo+Rsqj1SeLnjA3u1waSQ0pRyTQgGPw@????.?????.???>
Content-Type: text/plain; charset="UTF-8"
Jean,
I have worked all the XW and CAS Birds regularly with both Linearly and RHC
polarized antennas and using an SDR watching the entire passband, including
both the PSK and CW beacons.
The results with linear vs. RHC are nowhere nearly as "clean" as the 3 dB
you mention. Yes, it is certainly an advantage to have circular
polarization on all these linear birds, but the signal losses due to
polarization issues is often a very small part of the problem.
I have observed, routinely, linear birds dropping into the noise on RHC ,
that are 15 to 20 dB louder on linear vertical polarization. Then, within
20 or 30 seconds, the opposite is true. The only satellites where I see
circular polarization "consistently" stronger than linear is with the
weather sats, like NOAA-18, and I believe they are truly circular
polarization on the Transmitter.
While the text books say Linear > RHC is max of 3 dB loss, there are so
many other factors to consider that have dramatic effects on the rx signal
strength as to make the theoretical 3 dB difference non-existent over short
time intervals.
I have hours of passband recordings that show the following effects:
1. Uplink vs Downlink differential polarization
2. Shading of the satellite antennas by the body of the satellite.
3. Profound tumbling of the satellite (as in XW-2F).
4. Tropospheric Ducting at low incident angles preventing the signal
arriving at ground level antennas
I am sure there are other factors. The one thing that is provably clear:
the 3 dB loss of RHC to Linear is rarely evident on any of the LEOs that I
use. It can much, much, much more or much much less, but the 3 dB
theoretical is rarely evident on the LEOs.
I'm not saying RHC is undesirable on the rx end. It is VERY desirable based
on my observations. It can show 10 to 15 dB increase over a linear antenna
(at times). These times are NOT predictable and the duration is often less
than 20 or 30 seconds, when the RHC antenna signal disappears when a
vertically polarized antenna is quite strong.
Neither am I saying that this is all polarization...it clearly is not. What
I am saying is don't expect to wipe out massive changes in rx or tx signal
strength on the LEOs by using circular polarization. It can seem to help.
It can seem to hurt. It can do absolutely nothing. All of which happen over
very short (< 15 to 30 sec) intervals.
There are so many other confounding variables that any claims for practical
on the ground signal improvement due only to Linear > RHC polarization
changes just don't show up. They are masked by these other variables.
Why am I bothering to go through all this explanation of my own experience?
Because if someone goes out and spends $500 on RHC up and downlink
antennas, with the expectation that their deep fades are going to limited
to 3 dB against these linear birds....it is NOT going to happen....and they
are going to be quite unhappy.
73, N0AN
Hasan
On Tue, Sep 24, 2019 at 7:52 AM Jean Marc Momple via AMSAT-BB <
amsat-bb@?????.???> wrote:
> Rich,
>
> Most of the birds (VHF/UHF) are using dipoles or monopoles which are
> linear polarisation. The reasons to use circular polarisation is to reduce
> deep fades and the convention for HAMs is to use RHCP, some also use
> antennas which can be switch between RHCP & LHCP but the difference is
> generally quite small except if the satellite has circular polarisation
> antennas.
>
> To explain a bit more: if you use linear polarisation at your ground
> station, due to the spinning and/or tumbling of the bird the fades may be
> up to 30dB but if you use circular the fades will be about 3 dB max.
>
> 73
>
>
> Jean Marc (3B8DU)
>
> > On Sep 24, 2019, at 6:01 AM, RG via AMSAT-BB <amsat-bb@?????.???> wrote:
> >
> > Hi,I was thinking about getting the my eggbeater antenna,One thing I was
> hesitant about it is that it does just RHP.Is it that most Leo's use RHP?I
> have no idea what satellites have RHP or LHP,If anyone can tell me where I
> can find that info that would be helpful.Please excuse my
> ignorance.ThanksRich
> > marzo7088@?????.???
> > _______________________________________________
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> > to all interested persons worldwide without requiring membership.
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> AMSAT-NA.
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>
> _______________________________________________
> Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available
> to all interested persons worldwide without requiring membership. Opinions
> expressed
> are solely those of the author, and do not reflect the official views of
> AMSAT-NA.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
>
------------------------------
Subject: Digest Footer
_______________________________________________
Sent via amsat-bb@?????.???.
AMSAT-NA makes this open forum available to all interested persons worldwide
without requiring membership. Opinions expressed
are solely those of the author, and do not reflect the official views of
AMSAT-NA.
Not an AMSAT member? Join now to support the amateur satellite program!
https://www.amsat.org/mailman/listinfo/amsat-bb
------------------------------
End of AMSAT-BB Digest, Vol 14, Issue 361
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