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CX2SA > SATDIG 30.05.18 15:08l 847 Lines 27812 Bytes #999 (0) @ WW
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Sent: 180530/1304Z @:CX2SA.SAL.URY.SOAM #:44018 [Salto] FBB7.00e $:AMSATBB13181
From: CX2SA@CX2SA.SAL.URY.SOAM
To : SATDIG@WW
Today's Topics:
1. Re: LongJiang and Doppler correction (Dimitry Borzenko)
2. Re: Emails from AMSAT Website (Larry Howell)
3. Re: Emails from AMSAT Website (John)
4. Re: Emails from AMSAT Website (skristof@???????.????
5. Re: Emails from AMSAT Website (Alan)
6. Re: LongJiang and Doppler correction (Mike Rupprecht)
7. Re: Emails from AMSAT Website (Joe Fitzgerald)
8. Re: LongJiang and Doppler correction (Dimitry Borzenko)
----------------------------------------------------------------------
Message: 1
Date: Wed, 30 May 2018 08:35:38 +0000
From: "Dimitry Borzenko" <dibor@?????.???>
To: "AMSAT BB" <amsat-bb@?????.???>
Subject: Re: [amsat-bb] LongJiang and Doppler correction
Message-ID: <em9830f8da-4834-498c-8572-e1e51482e2c6@???????????>
Content-Type: text/plain; format=flowed; charset=utf-8
Hello.
Have problem with running Live CD.
Have made USB bootable diskONkey , system is runs.
Mun Downlink Proxy is configured and Orbit TLE can be downloaded, but
ALL ports is NOT connected!
RTL is running and freq. calibrated.
Also while running Decoder got 4 terminals running and have some message
about "File is not find or EOF ....."
What I did wrong?
de 4z5cp.
------ Original Message ------
From: "Scott" <scott23192@?????.???>
To: "AMSAT BB" <amsat-bb@?????.???>
Sent: 30.05.2018 2:30:33
Subject: Re: [amsat-bb] LongJiang and Doppler correction
>Hi Jean Marc.
>
>I have tried to follow the news of these lunar satellites. While
>several of the guys with DSN capability have received the S-Band
>downlinks, I'm not aware of anyone hearing anything on 70cm past the
>first day as the sats left Earth.
>
>In fact, even though I am listening every night for the 70cm telemetry
>(using the team's GNU Radio flowgraphs), I have not heard any
>confirmation that the 70cm transmitter is even on (telemetry -or- JT4).
>
>-Scott, K4KDR
>
>
>=======================================================
>
>-----Original Message----- From: Jean Marc Momple
>Sent: Tuesday, May 29, 2018 12:37 PM
>To: AMSAT BB
>Subject: Re: [amsat-bb] LongJiang and Doppler correction
>
>Dear All,
>
>May be a stupid question for the experts, but genuine from me.
>
>Has anyone received any FT4G beacon signal from the Longiang Sats so
>far?
>
>I have being trying to do so for the past week without success.
>
>73
>
>
>Jean Marc (3B8DU)
>
>
>
>
>>On May 26, 2018, at 8:54 PM, Nico Janssen <hamsat@??????.??> wrote:
>>
>>
>>In the coming days the doppler shift on the 70 cm downlink of
>>LongJiang 2 will vary between +2000 and -2200 Hz (for my QTH).
>>This can easily be calculated with GMAT using the script I published
>>a couple of hours ago (see my earlier post).
>>
>>73,
>>Nico PA0DLO
>>
>>On 26-05-18 17:44, charlie@??????????????.???????????.??.?? wrote:
>>>Michael
>>>
>>>I think that there are three main components to the Doppler shift for
>>>a
>>>satellite orbiting the moon.
>>>
>>>1. Earth rotation moving the observer toward the moon at moonrise
>>>(+ve
>>>Doppler) and moonset (-ve).
>>>
>>>2. Earth-moon distance variation (smaller than 1, and very slowly
>>>changing in comparison).
>>>
>>>3. Orbital velocity of the satellite itself.
>>>
>>>1 and 2 are easy to work out using EME software, eg WSJT-X or
>>>Moonsked. I
>>>can't help with 3.
>>>
>>>Taking today as an example, total of 1 and 2 for the moon vary from ~
>>>+3
>>>to -4.5kHz at S-Band.
>>>
>>>With DSN satellites many of us use(d) JPL Horizons to calculate
>>>Doppler
>>>shift for Deep Space missions. Observing the Doppler shift change
>>>when
>>>probes were captured by the target planet was quite interesting (a
>>>slowly
>>>changing shift to a cyclic one).
>>>
>>>73
>>>
>>>Charlie G3WDG
>>>
>>> > I find that an interesting question. One would think that since the
>>>moon
>>>>orbits the earth at a much much slower rate than a satellite that
>>>>there
>>>>would be almost no Doppler correction required. If you compensate
>>>>for the
>>>>speed of the orbit around the moon that is also at a much lower
>>>>speed than
>>>>a Earth satellite would be traveling at. Earth satellites are in the
>>>>17,000 mph range and moon satellites are in the 2000 mile an hour
>>>>range
>>>>orbiting speed. Also the chance that the satellite orbiting the moon
>>>>could
>>>>be at such an axis where it is in full visibility the earth the
>>>>whole
>>>>time, at that point there would not be a Doppler correction based
>>>>upon
>>>>satellite velocity only the moon's velocity. Will be interesting to
>>>>hear
>>>>the experts chime in on this.
>>>>
>>>>Michael Vivona
>>>>Sent from my iPad
>>>>
>>>>On May 25, 2018, at 5:49 PM, Stefan Wagener <wageners@?????.???>
>>>>wrote:
>>>>
>>>>The problem will not be the pointing (you could just point to the
>>>>moon :-)
>>>>Pending distance, speed and orbit around the moon and position to
>>>>earth,
>>>>you might have a difficult time adjusting for doppler. I let more
>>>>knowledgable folks chip in on this one.
>>>>
>>>>Stefan, VE4NSA
>>>>
>>>>>On Fri, May 25, 2018 at 2:40 PM Jordan Trewitt
>>>>><jmtrewitt@?????.???>
>>>>>wrote:
>>>>>
>>>>>If it was the 70 cm downlink, you might be able to schedule
>>>>>something
>>>>>with
>>>>>someone else's SATNOGS station (idk how that'd work with getting a
>>>>>rotator
>>>>>to work though), if they have a large enough yagi that is.
>>>>>-Jordan
>>>>>KF5COQ
>>>>>
>>>>>>On Fri, May 25, 2018, 12:46 PM Zach Metzinger <zmetzing@?????.???>
>>>>>>wrote:
>>>>>>
>>>>>>>On 05/25/18 11:25, Nico Janssen wrote:
>>>>>>>
>>>>>>>It is confirmed from China that LongJiang 2 has performed a
>>>>>>>successful braking maneuver, so that it is now in lunar orbit.
>>>>>>>No further details yet.
>>>>>>Nico,
>>>>>>
>>>>>>Do you know of any WebSDRs which are pointed and tuned to the
>>>>>>downlink
>>>>>>signals?
>>>>>>
>>>>>>73,
>>>>>>
>>>>>>--- 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: http://www.amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 2
Date: Tue, 29 May 2018 22:48:04 -0400
From: Larry Howell <larry.howell.47@?????.???>
To: amsat-bb@?????.???
Subject: Re: [amsat-bb] Emails from AMSAT Website
Message-ID:
<CAMiRMkKJYunWHmoGbGPSUfqLn=Va44jH8fiP_pd+6e98HJjpQw@????.?????.???>
Content-Type: text/plain; charset="UTF-8"
Both an email list and a forum are useful to many of us who have a
broadband Internet connection. However, I have friends only 40 miles away
in rural areas that can't use a web-based forum because they have limited
bandwidth DSL or dial-up connections. Web-based applications are too slow
to update to be of any use to them. If the email goes away, they're
effectively cut off.
Larry AC8YE
On Tue, May 29, 2018 at 10:30 PM, John Brier <johnbrier@?????.???> wrote:
> I don't mind sticking with the email list. We have web forums if you need
> to do fancy formatting:
>
> https://forums.qrz.com/index.php?forums/satellite-and-
> space-communications.69/
>
> I believe recently someone had trouble formatting something here so they
> posted it there and linked to it from here. It happens so infrequently I
> don't think it's worth the change.
>
> I have amsat-bb go straight to my inbox unfiltered because I like to stay
> up on AMSAT activities. I also have notifications on the QRZ satellite
> forum, but I have to leave my email app on my phone to do anything with it,
> and the web interface isn't great on mobile IIRC. Email is simple and easy.
>
> They each have their merits.
>
> 73, John Brier KG4AKV
>
> On Tue, May 29, 2018 at 7:49 PM, Ken M <va7kbm@???????.???> wrote:
>
> > Hello all,
> >
> > These and many other email issues are why, IMHO, the current old-style
> > AMSAT mailing list should be converted to a more modern web-based forum
> > that can be organized by topic.
> >
> > 73 Ken VA7KBM
> >
> > On May 29, 2018, at 2:28 PM, Zach Metzinger <zmetzing@?????.???<???????
> zme
> > tzing@?????.???>> wrote:
> >
> > On 05/29/18 16:33, Vince Fiscus, KB7ADL wrote:
> > And just as a side note, when the email issue is solved, another
> > re-look at why some messages come through with no CR or line feeds.
> > (ie. formatting)
> >
> > Hello Vince,
> >
> > This is likely a side-effect of the MIME processing in your email
> > client. Mike's email was base64 encoded and sent to the list by
> > Thunderbird 52.8.0 (from headers).
> >
> > Content-Transfer-Encoding: base64
> > Content-Type: text/plain; charset="utf-8"; Format="flowed"
> > <...>
> > TWUgdG9vLCBObyByZXBseSEKCk1pa2UsIEFCOVYKCgpPbiA1LzI5LzIwMTgg
> > MTU6MjYgUE0sIFNj
> > b3R0IHdyb3RlOgo+IFRoYW5rcyBmb3IgdGhlIGluZm8sIF
> > BhdWwhCj4KPiBBcyBhIGNoZWNrLCBJ
> > IHRyaWVkIHRvIGxvZyBpbiBhbmQgbXkgY3VycmVudCBwYXNzd29yZCB3YXMg
> > bm90IGFjY2VwdGVk
> > Lgo+Cj4gSSBjbGlja2VkIHRoZSBQYXNzd29yZCBSZXNldCBidXR0b24gYW5kIGl0
> > IGluZGljYXRl
> >
> > This "line noise" is reconstituted into his email message at your end
> > and laid out on your screen by your email program.
> >
> > Mike's email shows up just fine for me in Thunderbird 45.5.1 and Mutt
> > 1.7.1 (2016-10-04).
> >
> > Have you tried looking at his message using your provider's web mail
> > interface? Does it look correct there?
> >
> > --- 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: http://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: http://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: http://www.amsat.org/mailman/listinfo/amsat-bb
>
------------------------------
Message: 3
Date: Wed, 30 May 2018 11:28:20 +0100
From: "John" <john@?????.???.??>
To: <amsat-bb@?????.???>
Subject: Re: [amsat-bb] Emails from AMSAT Website
Message-ID: <01db01d3f800$ee732b90$cb5982b0$@?????.???.??>
Content-Type: text/plain; charset="us-ascii"
To further add to this point, many of us do not have time to constantly
refresh and browse a web forum, whereas an e-mail list effectively pushes
each update to you one at a time, allowing a much easier use format.
I stopped using forums years ago, but still read e-mail reflectors as they
come in with all my other e-mail in one useful place.
73,
John (XLX)
-----Original Message-----
From: AMSAT-BB <amsat-bb-bounces@?????.???> On Behalf Of Larry Howell
Sent: 30 May 2018 03:48
To: amsat-bb@?????.???
Subject: Re: [amsat-bb] Emails from AMSAT Website
Both an email list and a forum are useful to many of us who have a broadband
Internet connection. However, I have friends only 40 miles away in rural
areas that can't use a web-based forum because they have limited bandwidth
DSL or dial-up connections. Web-based applications are too slow to update
to be of any use to them. If the email goes away, they're effectively cut
off.
Larry AC8YE
On Tue, May 29, 2018 at 10:30 PM, John Brier <johnbrier@?????.???> wrote:
> I don't mind sticking with the email list. We have web forums if you
> need to do fancy formatting:
>
> https://forums.qrz.com/index.php?forums/satellite-and-
> space-communications.69/
>
> I believe recently someone had trouble formatting something here so
> they posted it there and linked to it from here. It happens so
> infrequently I don't think it's worth the change.
>
> I have amsat-bb go straight to my inbox unfiltered because I like to
> stay up on AMSAT activities. I also have notifications on the QRZ
> satellite forum, but I have to leave my email app on my phone to do
> anything with it, and the web interface isn't great on mobile IIRC. Email
is simple and easy.
>
> They each have their merits.
>
> 73, John 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:
> > http://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:
> > http://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: http://www.amsat.org/mailman/listinfo/amsat-bb
>
_______________________________________________
Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available to al:amsat-bb-bounces@?????.???? On Behalf Of
<skristof@???????.???
<Sent: Wednesday, May 30, 2018 06:16 AM
<To: Paul Stoetzer <n8hm@????.???>; AMSAT BB <amsat-bb@?????.???>
<Subject: Re: [amsat-bb] Emails from AMSAT Website
<
<We got off on a tangent about carriage returns, etc.
<
<I'm still wondering if anyone is working the problem with passwords at
<the AMSAT store.
<
<Steve AI9IN
<
<On 2018-05-29 15:52, skristof@???????.??? wrote:
<
<> You state that "there is no need to take any action", but my password
<> doesn't work anymore. So, I or someone in charge of the AMSAT store need
<> to take some kind of action. Recommendation?
<>
<> Steve AI9IN
<>
<> On 2018-05-29 14:50, Paul Stoetzer wrote:
<>
<>> Good afternoon,
<>>
<>> Many of you have received an email stating that your AMSAT website
<>> password had been changed. These emails were automatically generated
<>> during the final merge of our old membership database into our new
<>> system. There is no need to take any action.
<>>
<>> We apologize for any inconvenience.
<>>
<>> 73,
<>>
<>> Paul Stoetzer, N8HM
<>> Executive Vice President
<>> Radio Amateur Satellite Corporation (AMSAT)
<>> _______________________________________________
<> _______________________________________________
<> 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: http://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: http://www.amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 6
Date: Wed, 30 May 2018 13:56:51 +0200
From: "Mike Rupprecht" <mail@??????????????.??>
To: "'Dimitry Borzenko'" <dibor@?????.???>, "'AMSAT BB'"
<amsat-bb@?????.???>
Subject: Re: [amsat-bb] LongJiang and Doppler correction
Message-ID: <004e01d3f80d$4cbd1600$e6374200$@??>
Content-Type: text/plain; charset="iso-8859-1"
Hi Dimitry,
TLE are useles in lunar orbit.
You have to update the tracking file in all four decoders.
https://github.com/bg2bhc/dslwp_doc/blob/master/program_tracking_dslwp-b_201
80529.txt
(or later files)
73 Mike
DK3WN
-----Urspr?ngliche Nachricht-----
Von: AMSAT-BB [mailto:amsat-bb-bounces@?????.???? Im Auftrag von Dimitry
Borzenko
Gesendet: 30 May 2018 10:36
An: AMSAT BB
Betreff: Re: [amsat-bb] LongJiang and Doppler correction
Hello.
Have problem with running Live CD.
Have made USB bootable diskONkey , system is runs.
Mun Downlink Proxy is configured and Orbit TLE can be downloaded, but ALL
ports is NOT connected!
RTL is running and freq. calibrated.
Also while running Decoder got 4 terminals running and have some message
about "File is not find or EOF ....."
What I did wrong?
de 4z5cp.
------ Original Message ------
From: "Scott" <scott23192@?????.???>
To: "AMSAT BB" <amsat-bb@?????.???>
Sent: 30.05.2018 2:30:33
Subject: Re: [amsat-bb] LongJiang and Doppler correction
>Hi Jean Marc.
>
>I have tried to follow the news of these lunar satellites. While
>several of the guys with DSN capability have received the S-Band
>downlinks, I'm not aware of anyone hearing anything on 70cm past the
>first day as the sats left Earth.
>
>In fact, even though I am listening every night for the 70cm telemetry
>(using the team's GNU Radio flowgraphs), I have not heard any
>confirmation that the 70cm transmitter is even on (telemetry -or- JT4).
>
>-Scott, K4KDR
>
>
>=======================================================
>
>-----Original Message----- From: Jean Marc Momple
>Sent: Tuesday, May 29, 2018 12:37 PM
>To: AMSAT BB
>Subject: Re: [amsat-bb] LongJiang and Doppler correction
>
>Dear All,
>
>May be a stupid questio to the
>>>>>>downlink signals?
>>>>>>
>>>>>>73,
>>>>>>
>>>>>>--- 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: http://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: http://www.amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 7
Date: Wed, 30 May 2018 08:18:55 -0400
From: Joe Fitzgerald <jfitzgerald@????.???.???>
To: amsat-bb@?????.???
Subject: Re: [amsat-bb] Emails from AMSAT Website
Message-ID: <b049c8c0-351c-42d0-cfa8-673424b6dce3@????.???.???>
Content-Type: text/plain; charset=utf-8
On 5/30/2018 7:16 AM, skristof@???????.??? wrote:
> We got off on a tangent about carriage returns, etc.
>
> I'm still wondering if anyone is working the problem with passwords at
> the AMSAT store.
>
Yes, Steve.? People are quite literally losing sleep over it.??
We are trying to figure out if we can restore passwords from backup
files without affecting anyone who has done a password reset in response
to yesterday's e-mails.
Should anyone have any urgent purchases to complete, send a note to
webmaster@?????.??? and we will work to get your order through manually.
de KM1P Joe
------------------------------
Message: 8
Date: Wed, 30 May 2018 12:57:40 +0000
From: "Dimitry Borzenko" <dibor@?????.???>
To: "Mike Rupprecht" <mail@??????????????.??>, "'AMSAT BB'"
<amsat-bb@?????.???>
Subject: Re: [amsat-bb] LongJiang and Doppler correction
Message-ID: <emd6a0502d-6428-4e7e-9801-bf6a92d789ba@???????????>
Content-Type: text/plain; format=flowed; charset=utf-8
Hello Mike.
I saw new files but I do not know where I should to put this file (which
folder?).
Regards.
------ Original Message ------
From: "Mike Rupprecht" <mail@??????????????.??>
To: "'Dimitry Borzenko'" <dibor@?????.???>; "'AMSAT BB'"
<amsat-bb@?????.???>
Sent: 30.05.2018 14:56:51
Subject: AW: [amsat-bb] LongJiang and Doppler correction
>Hi Dimitry,
>
>TLE are useles in lunar orbit.
>
>You have to update the tracking file in all four decoders.
>
>https://github.com/bg2bhc/dslwp_doc/blob/master/program_tracking_dslwp-b_201
>80529.txt
>
>(or later flowgraphs), I have not heard any
>>confirmation that the 70cm transmitter is even on (telemetry -or-
>>JT4).
>>
>>-Scott, K4KDR
>>
>>
>>=======================================================
>>
>>-----Original Message----- From: Jean Marc Momple
>>Sent: Tuesday, May 29, 2018 12:37 PM
>>To: AMSAT BB
>>Subject: Re: [amsat-bb] LongJiang and Doppler correction
>>
>>Dear All,
>>
>>May be a stupid question for the experts, but genuine from me.
>>
>>Has anyone received any FT4G beacon signal from the Longiang Sats so
>>far?
>>
>>I have being trying to do so for the past week without success.
>>
>>73
>>
>>
>>Jean Marc (3B8DU)
>>
>>
>>
>>
>>>On May 26, 2018, at 8:54 PM, Nico Janssen <hamsat@??????.??> wrote:
>>>
>>>
>>>In the coming days the doppler shift on the 70 cm downlink of
>>>LongJiang 2 will vary between +2000 and -2200 Hz (for my QTH).
>>>This can easily be calculated with GMAT using the script I published
>>>a
>>>couple of hours ago (see my earlier post).
>>>
>>>73,
>>>Nico PA0DLO
>>>
>>>On 26-05-18 17:44, charlie@??????????????.???????????.??.?? wrote:
>>>>Michael
>>>>
>>>>I think that there are three main components to the Doppler shift
>>>>for
>>>>a satellite orbiting the moon.
>>>>
>>>>1. Earth rotation moving the observer toward the moon at moonrise
>>>>(+ve
>>>>Doppler) and moonset (-ve).
>>>>
>>>>2. Earth-moon distance variation (smaller than 1, and very slowly
>>>>changing in comparison).
>>>>
>>>>3. Orbital velocity of the satellite itself.
>>>>
>>>>1 and 2 are easy to work out using EME software, eg WSJT-X or
>>>>Moonsked. I can't help with 3.
>>>>
>>>>Taking today as an example, total of 1 and 2 for the moon vary from
>>>>~
>>>>+3
>>>>to -4.5kHz at S-Band.
>>>>
>>>>With DSN satellites many of us use(d) JPL Horizons to calculate
>>>>Doppler shift for Deep Space missions. Observing the Doppler shift
>>>>change when probes were captured by the target planet was quite
>>>>interesting (a slowly changing shift to a cyclic one).
>>>>
>>>>73
>>>>
>>>>Charlie G3WDG
>>>>
>>>> > I find that an interesting question. One would think that since
>>>> > the
>>>>moon
>>>>>orbits the earth at a much much slower rate than a satellite that
>>>>>there would be almost no Doppler correction required. If you
>>>>>compensate for the speed of the orbit around the moon that is also
>>>>>at a much lower speed than a Earth satellite would be traveling at.
>>>>>Earth satellites are in the 17,000 mph range and moon satellites
>>>>>are
>>>>>in the 2000 mile an hour range orbiting speed. Also the chance that
>>>>>the satellite orbiting the moon could be at such an axis where it
>>>>>is
>>>>>in full visibility the earth the whole time, at that point there
>>>>>would not be a Doppler correction based upon satellite velocity
>>>>>only
>>>>>the moon's velocity. Will be interesting to hear the experts chime
>>>>>in on this.
>>>>>
>>>>>Michael Vivona
>>>>>Sent from my iPad
>>>>>
>>>>>On May 25, 2018, at 5:49 PM, Stefan Wagener <wageners@?????.???>
>>>>>wrote:
>>>>>
>>>>>The problem will not be the pointing (you could just point to the
>>>>>moon :-) Pending distance, speed and orbit around the moon and
>>>>>position to earth, you might have a difficult time adjusting for
>>>>>doppler. I let more knowledgable folks chip in on this one.
>>>>>
>>>>>Stefan, VE4NSA
>>>>>
>>>>>>On Fri, May 25, 2018 at 2:40 PM Jordan Trewitt
>>>>>><jmtrewitt@?????.???>
>>>>>>wrote:
>>>>>>
>>>>>>If it was the 70 cm downlink, you might be able to schedule
>>>>>>something with someone else's SATNOGS station (idk how that'd work
>>>>>>with getting a rotator to work though), if they have a large
>>>>>>enough
>>>>>>yagi that is.
>>>>>>-Jordan
>>>>>>KF5COQ
>>>>>>
>>>>>>>On Fri, May 25, 2018, 12:46 PM Zach Metzinger
>>>>>>><zmetzing@?????.???>
>>>>>>>wrote:
>>>>>>>
>>>>>>>>On 05/25/18 11:25, Nico Janssen wrote:
>>>>>>>>
>>>>>>>>It is confirmed from China that LongJiang 2 has performed a
>>>>>>>>successful braking maneuver, so that it is now in lunar orbit.
>>>>>>>>No further details yet.
>>>>>>>Nico,
>>>>>>>
>>>>>>>Do you know of any WebSDRs which are pointed and tuned to the
>>>>>>>downlink signals?
>>>>>>>
>>>>>>>73,
>>>>>>>
>>>>>>>--- Zach
>>>>>>>N0ZGO
>>
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------------------------------
Subject: Digest Footer
_______________________________________________
Sent via amsat-bb@?????.???.
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without requiring membership. Opinions expressed
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AMSAT-NA.
Not an AMSAT member? Join now to support the amateur satellite program!
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------------------------------
End of AMSAT-BB Digest, Vol 13, Issue 18lada "Dominum et vivificantem".
1990 Terremotos en Peru y Rumania que ocasionan decenas de muertos.
1994 Muere el escritor uruguayo Juan Carlos Onetti.
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"If a nation values anything more than freedom, it will lose its freedom; and
the irony of it is that if it is comfort or money it values more, it will
lose that, too."
-- W. Somerset Maugham
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