[amsat-bb] LongJiang and Doppler correction

Thu May 31 00:44:45 UTC 2018

So it sounds like they're getting ready for some more tests with this tweet
from BG2BHC:

DSLWP Live CD update, for the tests comming this weekend
https://t.co/Tjw5Yo9VfT @AMSAT @AmsatUK @cgbassa @dk3wn @n6rfm @ndonso
@ea4gpz @m6sig @JA5BLZ

Best regards,
Jordan Trewitt
KF5COQ

On Wed, May 30, 2018, 11:08 AM Dimitry Borzenko <dibor at iname.com> wrote:

> Hi Mike.
> I have pointing Program Tracking CC of all decoders to the
> program_tracking_dslwp-b.txt file
> For me is more simple to change new downloaded file to
> "program_tracking_dslwp-b.txt" and overwrite existed then change path in
> the Program Tracking CC block of 2 or 4 decoders.
>
> Thank you for the help!
>
>
> ------ Original Message ------
> From: "Mike Rupprecht" <mail at mike-rupprecht.de>
> To: "'Dimitry Borzenko'" <dibor at iname.com>; "'AMSAT BB'"
> <amsat-bb at amsat.org>
> Sent: 30.05.2018 18:46:13
> Subject: AW: AW: AW: [amsat-bb] LongJiang and Doppler correction
>
> >Hi Dimitry,
> >
> >of course - you need the full path + filename ...
> >
> >Wei, BG2BHC is updating the files regularly. If you take a look into
> >such a tracking file you see seven columns in each line. The first
> >column contains the date and time in Unix timestamp format. The next 3
> >columns contain the position in ECEF coordinates followed by 3 columns
> >which contain the velocity in ECEF coordinates. Based on the filename
> >you can see how long this file can be used.
> >
> >You will get this error message (File is not find or EOF .....)  if no
> >valid information is found that match to the current time.
> >
> >73 Mike
> >
> >
> >-----Ursprüngliche Nachricht-----
> >Von: Dimitry Borzenko [mailto:dibor at iname.com]
> >Gesendet: 30 May 2018 17:10
> >An: Mike Rupprecht; 'AMSAT BB'
> >Betreff: Re: AW: AW: [amsat-bb] LongJiang and Doppler correction
> >
> >Hi Mike.
> >Understood.
> >Program Tracking CC block request exact file, path is not enough.
> >I should to change every day/ two days Program Tracking CC setting for
> >each demodulator?
> >Or I do not understand something?
> >
> >Regards.
> >
> >------ Original Message ------
> >From: "Mike Rupprecht" <mail at mike-rupprecht.de>
> >To: "'Dimitry Borzenko'" <dibor at iname.com>; "'AMSAT BB'"
> ><amsat-bb at amsat.org>
> >Sent: 30.05.2018 17:23:48
> >Subject: AW: AW: [amsat-bb] LongJiang and Doppler correction
> >
> >>Dimitry,
> >>
> >>the default directory is /home/lilac/lilacsat/gr-dslwp/examples/
> >>Edit the correct path in the Program Tracking CC block.
> >>
> >>73 Mike
> >>DK3WN
> >>
> >>-----Ursprüngliche Nachricht-----
> >>Von: Dimitry Borzenko [mailto:dibor at iname.com]
> >>Gesendet: 30 May 2018 14:58
> >>An: Mike Rupprecht; 'AMSAT BB'
> >>Betreff: Re: AW: [amsat-bb] LongJiang and Doppler correction
> >>
> >>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 at mike-rupprecht.de>
> >>To: "'Dimitry Borzenko'" <dibor at iname.com>; "'AMSAT BB'"
> >><amsat-bb at amsat.org>
> >>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 files)
> >>>
> >>>73 Mike
> >>>DK3WN
> >>>
> >>>-----Ursprüngliche Nachricht-----
> >>>Von: AMSAT-BB [mailto:amsat-bb-bounces at amsat.org] 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 at gmail.com>
> >>>To: "AMSAT BB" <amsat-bb at amsat.org>
> >>>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 at xs4all.nl> 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 at sucklingfamily.free-online.co.uk 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 at gmail.com>
> >>>>>>>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 at gmail.com>
> >>>>>>>>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 at pobox.com>
> >>>>>>>>>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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> >>>>to all interested persons worldwide without requiring membership.
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> >>>>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!
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> >>>
> >>>_______________________________________________
> >>>Sent via AMSAT-BB at amsat.org. 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!
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> >>>
> >>
> >
>
> _______________________________________________
> Sent via AMSAT-BB at amsat.org. 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!
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>