AMSAT-BB January 2008

218 participants
332 discussions

BBS inefficiency -vs- PACSAT protocol
by Robert Bruninga 30 Jan '08

30 Jan '08

>> It is extremely inefficient to attempt to logon >> to [the ISS] BBS over Europe/USA since it blocks >> other users from the more efficient digipeater >> mode designed for those high density areas. > > This Apples and Oranges comparison. There is a huge > difference between a Store-And-Forward Mail box and an > Unacknowledged Broadcast packet. With an Unproto > Packet you never know if anyone heard your one-way > packet. Ah, but you do. You see it in the downlink. Congestion on the ISS packet system is only on the uplink. Rarely if ever on the downlink. If you see it in the downlink, then everyone else and the recepient should have seen it too... Very efficient without needing ACKS and RETRIES and CONNECTIONS, and CONNECT REQUESTS, and TIMEOUTS, and REJECT packets.. > Store-And-Forward packet mail has a whole different > set of uses. We used Packet Mail on Space Station Mir > for 10+ years.... Yes, but back then the crew had no other alternative for email. Now they have easy email 24/7. But I agree, it "works" fine, but one has to be careful how we define "works". Over the USA or Europe, it only works for one user and only if that user has killowatts of ERP to step on all other packets to complete his connection (or lives in Hawaii, or other island nation surrounded by no other users within 1200 miles). > The ISS Packet Mail project never caught on > because we had Hardware and software problems > with the TNC's and we never were assigned > a dedicated Laptop. ... The current system can > only support 1 mail box user at a time. But even with only one, in a congestion environment and the requirement for ACKS of every line received, the success rate for the average user is so low and frustration level so high, that it is impractical for the common user and all the lost packets and retries consume the entire pass at the expense of everyone else on frequency. > Marex has received initial approval to upgrade the > system to a Kantronics System that will support 5+ > mail box users and also includes full remote control > from ground System Operators. A worthy goal, but that will only multiply the existing impracticality by a factor of 5 in QRM and virtually nothing will get through (unless there is a drastic change to the protocol). That is why ALL flying BBS's since the mid 1980's use the PACSAT protocol which avoids all of the congestion issues of the normal AX.25 CONNECTED style BBS. The PACSAT protocol: 1) Continuously streams the MAIL List. 2) Allows everyone to capture the MAIL list passively without having to transmit a single packet. 3) Everyones software captures every line from every file on the BBS and builds its own copy of the files. (still passively without transmitting a single packet). 4) As needed stations can requist "fills" of missing lines. Still all other stations also capture these "fills" to minimize the number of requests and repeats. 5) Ground software automatically manages the access to avoid user congestion on the uplink and software contributes to equal sharing of the BBS. 6) Discourteous users can not easily hog the asset. The result was the PACSAT protocol that allowed multiple accesses, by dozens of stations able to download megabytes per day and was efficient, and completely avoided all the ACK problems of terrestrial BBS's when flown in space. Every digital satellite since AO16 has used the PACSAT protocol for their store-and-forward BBS's: AO16, LO18, KO23, KO25, IO26, UO22, GO32, AO51 and others. There are very good, published and well thought our reasons for this. > If you would like to see a multiple user Mail box > on ISS please help support Marex, it's a > long road into space. My next hardware demo is > scheduled for Moscow in June 2008. This sounds like a great project, but only if such a multi-user BBS will take advantage of the lessons learned for more than 20 years in Amateur Space and avoid any BBS that requires line-by-line acknowledgment. If they can implement the multi-user scheme as used on the PACSATS for the last 20 years, then that will be a great advantage to users by at least an order of magnitude. Bob, WB4APR

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ISS Packet Digi-Path?
by Tony 30 Jan '08

30 Jan '08

All, What's the digi-path for the ISS? Is it RS0ISS-? or just ARISS? Thanks, Tony -K2MO

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Re: Ande Deorbit award received
by andy thomas 30 Jan '08

30 Jan '08

Mine safely received today too. A great reminder of a special event for us telemetry-chasers! ...Me mind on fire, me soul on fire Feelin' hot hot hot Party people, all around me Feelin' hot hot hot... 73 de andy g0SFJ __________________________________________________________ Sent from Yahoo! Mail - a smarter inbox http://uk.mail.yahoo.com

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Translation of FM satellite article going well
by OZ1MY 30 Jan '08

30 Jan '08

Hi all, As of now the article "Considerate operating practice" have reached Russia, Germany, UK, Spain and Italy :-) If you want to join in just send me an e-mail and I will send you the updated version. A large thanks to those who have responded already. See you on the satellites. 73 OZ1MY Ib

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25 watt Moonbounce
by Trevor 30 Jan '08

30 Jan '08

The story in the UK Scarborough Evening News about Angus Young M0IKB achieving Moonbounce with just 25 watts is a good illustration of the huge advances Amateurs have made in Moonbounce techniques over recent years. Not long ago it would have taken over 400 watts to achieve it. Why Angus is over the Moon - Scarborough Today (with picture of Angus) http://www.scarborougheveningnews.co.uk/news/Why-Angus-is-over-the.3686368.… Ham makes EME contact with just 25 watts http://www.southgatearc.org/news/january2008/record_eme_contact.htm The call book entry for Angus Young M0IKB can be seen at http://www.eham.net/callbook/M0IKB 73 Trevor M5AKA __________________________________________________________ Sent from Yahoo! Mail - a smarter inbox http://uk.mail.yahoo.com

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FO-29 schedule Feb.
by Mineo Wakita 30 Jan '08

30 Jan '08

Feb. UTC 1 2:10 - 2 3:00 - 3 2:06 - 4 none 5 3:45 - 6 2:50 - 7 3:45 - 8 2:46 - 9 3:36 - 10 2:42 - 11 3:33 - 12 none 13 3:28 - 14 2:33 - 15 3:23 - 16 2:30 - 17 3:20 - 18 none 19 3:15 - 20 2:20 - 21 3:10 - 22 2:15 - 23 3:05 - 24 3:55 - 25 none

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Long time eclipse prediction
by Chris Bloy 30 Jan '08

30 Jan '08

Hi All, I have never been able to get a straight answer on this one, but does InstantTrack or any other program show you the long term non-eclispse/eclispe period, or is there a way to calculate this? How do we know that PCSAT and UO11 are going to HIT sunlight or not for a period of time? I can see from Orbitron the realtime, but not anything in the future? Thanks, Chris

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Re: AO-27 Telem
by Mike Rupprecht 30 Jan '08

30 Jan '08

Hi Chris, yes, we should contact the AO-27 team and ask for the missing channel equations. Regarding your question for the MixW settings. I described this on my website - but it's in german. You can take a look at http://www.dk3wn.info/mixw_kiss.shtml But (it's easier for you) read here: http://www.mixw.co.uk/tune/tuneaprs/tuneaprs.html It's quite simple. I will write a decoding software for AO-27 (with KISS input) - the telemetry is similar to IO-26. You can see my decoding software here: http://www.dk3wn.info/software.shtml 73, Mike DK3WN -----Ursprüngliche Nachricht----- Von: Chris Bloy [mailto:[email protected]] Gesendet: Dienstag, 29. Januar 2008 21:42 An: 'Mike Rupprecht'; 'SV1BSX' Betreff: RE: [amsat-bb] Re: AO-27 Telem Hi Mike, Mak, Any idea on the setting for MixW as I cannot get anything to decode even close to your example? I think that we should have access to telemetry on this one, and would be willing to collect and build up a picture of what AO-27 is doing? Perhaps we should contact Amrad and ask? Thanks, Chris -----Original Message----- From: Mike Rupprecht [mailto:[email protected]] Sent: 29 January 2008 18:00 To: 'SV1BSX' Cc: 'Chris Bloy' Subject: AW: [amsat-bb] Re: AO-27 Telem Hi Mak, yes - and no. AO-27 send it's telemetry in non-AX.25 frames. There is no standard UI Frame and the most packet radio programs cannot decode this frames. BUT, you can use any TNC in KISS mode to generate a data file. The structure of AO-27 telemetry is similar to IO-26 or the other microsats. 1 Byte Channel number + 1 Byte channel value -> see my posting on AMSAT-BB. AND there are some soundcard solutions (e.g. MixW) to generate an KISS file. 73, Mike Dk3WN -----Ursprüngliche Nachricht----- Von: amsat-bb-bounces(a)amsat.org [mailto:[email protected]] Im Auftrag von SV1BSX Gesendet: Dienstag, 29. Januar 2008 15:55 An: Chris Bloy Cc: amsat-bb(a)amsat.org Betreff: [amsat-bb] Re: AO-27 Telem Hi Chris, I think it's impossible the receiving of TLM without a TNC (hardware). I tried also with "standalone" 1200Bps AFSK softwares for packet radio (like MIXW etc) without success. And yes, the TLM is "ON" just for a few seconds at the beginning (and at the end) of each "active" pass. 73, Mak SV1BSX ----- Original Message ----- From: "Chris Bloy" <chris(a)photofuture.co.uk> To: <amsat-bb(a)amsat.org> Sent: Tuesday, January 29, 2008 15:12 Subject: [amsat-bb] AO-27 Telem > Hi All, > > Can anyone tell me how to decode the telemetry from AO27? > > I have tried to use MIXW in Packet mode and RTTY mode, but all I seem to > get > is the date and nothing else? I even tried to feed it through AGWE to see > if > that would work.. I use AO27 all the time and use a minidisc recorder to > record my passes, and always capture the telem data at the end.. it would > be > good if someone could help me out on this one? > > Thanks, > > Chris > > _______________________________________________ > Sent via AMSAT-BB(a)amsat.org. Opinions expressed are those of the author. > Not an AMSAT-NA member? Join now to support the amateur satellite program! > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb > > > --- > avast! Antivirus: Inbound message clean. > Virus Database (VPS): 080127-0, 01/27/2008 > Tested on: 1/29/2008 15:54:42 > avast! - copyright (c) 1988-2008 ALWIL Software. > http://www.avast.com > > > --- avast! Antivirus: Outbound message clean. Virus Database (VPS): 080127-0, 01/27/2008 Tested on: 1/29/2008 16:55:20 avast! - copyright (c) 1988-2008 ALWIL Software. http://www.avast.com _______________________________________________ Sent via AMSAT-BB(a)amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb ____________ Virus checked by G DATA AntiVirusKit Version: AVK 18.2572 from 28.01.2008 Virus news: www.antiviruslab.com No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.19.15/1249 - Release Date: 29/01/2008 09:51 No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.19.15/1249 - Release Date: 29/01/2008 09:51 ____________ Virus checked by G DATA AntiVirusKit Version: AVK 18.2584 from 29.01.2008 Virus news: www.antiviruslab.com

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G6LVB Tracker Kits
by john 30 Jan '08

30 Jan '08

Hello, I currently use this interface with nova for windows. It works very well, but I have a problem with moving arrows on the keyboard or with the paddle of nova because no data is transmitted, is this normal? Thanks for your help john No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.19.15/1249 - Release Date: 29/01/2008 TiTi 09:51 -- Ce message a été vérifié par MailScanner pour des virus ou des polluriels et rien de suspect n'a été trouvé. MailScanner remercie transtec pour son soutien.

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29 Jan '08

Just in case anyone here is not on the HPSDR list... 73, Scotty WA2DFI *** TAPR ANNOUNCES PRODUCTION OF HPSDR PENELOPE BOARD *** High Performance Software Defined Radio Project (HPSDR) *IMPORTANT* 29 January 2008 TAPR and HPSDR need your input! You have until Sunday, February 5, 2008 at 0200 UTC to take action on this message and express interest to obtain a finished tested board, partial kit or bare PCB for this project. Production quantities will be determined by the collective expression of interest at this time. To register your interest you need to go to Dale's (WA8SRA) HAMSDR website, in the projects section. If you are a member and have previously expressed interest in these projects, log in and re-enter your Quantities of each board. NOTE: Previous quantities have been reset to zero so you WILL HAVE TO RE-ENTER QUANTITIES. If you are new to HPSDR and Dale's Website, please join for instant access by providing the information requested. Go NOW to: HTTP://www.hamsdr.com Login and go to Projects > TAPR-HPSDR and follow instructions provided on that page. What is HPSDR? http://hpsdr.org What is a Penelope? http://hpsdr.org/penelope.html There are many other HPSDR projects in design and testing; please see the HPSDR website for details.

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AMSAT-BB January 2008