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Eagle efficiencies
by McGrane 10 Sep '06

10 Sep '06

Greetings I personally prefer lower frequencies for satellite transmitters because of the lower path loss. Now, after viewing the power information on the eaglepedia meeting summary, I believe electrical efficiency is another good reason to support the lower frequencies. >From what I saw (probably estimates), the VHF transmitter will be about 60% efficient while the C band transmitter will be about 30% efficient. I was very happy to see a respectable 20 watts planned for the VHF output and the same for the C band transmitter. Thanks again to the design team. EEck out those watts and hope you have an alternative for power storage. Some bold new idea would be great. Patrick, N2OEQ

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APRS on ISS, PCSAT, and PCSAT2
by Armour, Randy (ITS) 10 Sep '06

10 Sep '06

I will apologize in advance as this question has probably been asked several times already. I am attempting to digi-peat through PCSAT, and PCSAT2 with an Arrow handheld and Kenwood D7A. Having no trouble using APRS on the ISS, I hope to be able to do the same with PCSAT and maybe even get through PCSAT2 before decommission. I can decode packets from PCSAT and PCSAT2, but never get a packet through either system. PCSAT had a 90 degree pass this morning, with no luck. I am suspicious that my packet path is incorrect, or I don't have enough power to reach the receivers. Packet path is ARISS,APRSAT,SGATE,WIDE. I was recently told that only ARISS was needed for PCSAT, PCSAT2, and ISS. Having no luck yet and time growing short for PCSAT2, I am hoping to get a definitive answer from the list. What is the correct packet path? Can I make it with such limited equipment as a handheld beam and 6 watt HT? Thanks in advance, Randy - KI4LMR

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Re: Two Sats
by w7lrd＠comcast.net 10 Sep '06

10 Sep '06

Hello I and a few others "played" with this concept back in the RS etc days. I forget (senior moment) the specific satellites and frequencies involved. I was though a bit complicated. Tracking two satellites (using a Commodore 64) and figuring muliple doppler effects, due to satellite relative speeds. Anyway it was a fun endeavor. With HEO's you could cover the whole planet. 73 Bob W7LRD Seattle -------------- Original message -------------- From: sco(a)sco-inc.com > If two sats like Hamsat (or Echo) were in orbit at the same time and > could see each other ... > > Could User#1 uplink to Sat-A and then Sat-A would link to Sat-B > (probably on one of the higher microwave bands) then Sat-B would > downlink to User#2 and User#2 would uplink to Sat-B and be relayed to > Sat-A and down to User#1 ?? > > If this could be done there would be a much larger footprint and > launch costs would be far less expensive, correct? > > Les W4SCO > > > _______________________________________________ > 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

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Po-28 no Heard
by Vincenzo Mone 10 Sep '06

10 Sep '06

Hi to the list, right now I have a pass of PO-28 but I do no hear any 9600 baud signal. It is a while that I do not hear it any more. Does anybody heard it or can tell me if is it still in good health? Thanks 73 de Enzo IK8OZV EasyLog 5 BetaTester EasyLog PDA BetaTester WinBollet BetaTester D.C.I. CheckPoint Regione Campania Skype: ik8ozv8520 *************************************** ***** GSM +39 338 9749786 ***** ***** SMS +39 338 9749786 ***** ***** FAX +39 328 7244294 ***** *** 2nd e-mail: vimone(a)tin.it *** ***************************************

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Re: The Eagle has died.
by i8cvs 10 Sep '06

10 Sep '06

----- Original Message ----- From: "Robert Oler" <cvn65vf94(a)msn.com> To: <vk6xh(a)arach.net.au>; <amsat-bb(a)amsat.org> Sent: Sunday, September 10, 2006 6:33 AM Subject: [amsat-bb] Re: The Eagle has died. > I sometimes look back on > the AO-40 Easy Sat articles (well written by Steve Ford) and smile. > > anyway intresting comments on your part. > > Robert Oler WB5MZO/portable > > Amsat Life member > Robert Oler WB5MZO Houston TX Hi Robert, WB5MZO In addition to the Steve Ford articles read please the article written by Antony Monteiro AA2TX in to QST september 2006 page-42 and smile again ! 73" de i8CVS Domenico

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[ans] ANS-253 AMSAT Weekly Bulletins
by Dee 10 Sep '06

10 Sep '06

AMSAT NEWS SERVICE ANS-253 ANS is a free, weekly, news and information service of AMSAT North America, The Radio Amateur Satellite Corporation. ANS reports on the activities of a worldwide group of Amateur Radio operators who share an active interest in designing, building, launching and communicating through analog and digital Amateur Radio satellites. Please send any amateur satellite news or reports to: ans-editor(a)amsat.org ****************** AMSAT 2006 Space Symposium ************************** Online registration and hotel reservation for the 2006 AMSAT Space Symposium has been posted to the AMSAT website, and information about the Symposium has been expanded. The 2006 AMSAT Space Symposium will be held October 6, 7 and 8 at the Crowne Plaza in Foster City California in the beautiful San Francisco Bay Area. Please visit http://www.amsat.org/amsat-new/symposium for additional information and an index to the expanded Symposium web pages. ************************************************************************ In this edition: * Mentor Graphics Makes Generous Donation * AMSAT Ballots due 9/15/06 * 2006 AMSAT Symposium * AO-51 PL Needed * Suit-Sat Re-enters * ARISS STATUS SB SAT @ AMSAT $ANS-253.01 Mentor Graphics Makes Generous Software Donation AMSAT News Service Bulletin 253.01 From AMSAT HQ SILVER SPRING, MD. September 10, 2006 To All RADIO AMATEURS BID: $ANS-253.01 AMSAT is very pleased to annouced an extremely generous donation of software tools from Mentor Graphics. Mentor Graphics has donated 20 licenses for entire suites of software with a total value in the hundreds of thousands of dollars! The software will used for the design, simulation, verification and test of circuits and multi-layer printed circuit boards for both the Eagle spacecraft as well as development of the User ground station for the digitial transponder. This software will be a great benefit to the Eagle and HPSDR team members working to develop the hardware that will make Eagle space and ground systems a reality. AMSAT thanks Mentor Graphics for their most generous donation. [ANS thanks Rick, W2GPS, for the above information] /EX SB SAT @ AMSAT $ANS-253.02 All AMSAT Ballots Due by Friday, 9/15/06 AMSAT News Service Bulletin 253.02 From AMSAT HQ SILVER SPRING, MD. September 10, 2006 To All RADIO AMATEURS BID: $ANS-253.02 Note to All AMSAT Members. Please make your vote count and get them mailed to AMSAT HQ by Friday, 9/15/06. Exercise your right to select your leadership and steer the group in the direction you feel is the proper course. Drop it in the mail now! Background on all the candidates can be found on the AMSAT web site to help your decisions. [ANS thanks Martha for the above information] /EX SB SAT @ AMSAT $ANS-253.03 2006 AMSAT Symposium AMSAT News Service Bulletin 253.03 From AMSAT HQ SILVER SPRING, MD. September 10, 2006 To All RADIO AMATEURS BID: $ANS-253.03 The annual Symposium is now about a month away. You can still sign up to attend this exciting event being held in San Francisco, CA. Meet all the leadeship and enjoy the classic talks given by superb speakers. Mingle with those that make satellites a reality-yes, real rocket scientists. All the information you need to join in this event are on the website. Stop by and read how to attend and see the great lineup of speakers and demonstrations that make this event unique. [ANS thanks Emily, N1DID, for the above information] /EX SB SAT @ AMSAT $ANS-253.04 AO-51 PL Needed AMSAT News Service Bulletin 253.04 From AMSAT HQ SILVER SPRING, MD. September 10, 2006 To All RADIO AMATEURS BID: $ANS-253.04 Remember that you need a PL of 67 Hz to access AO-51 in mode J-FM (except in QRP mode). Please, especially if you haven't worked a given satellite in mode J-FM before, make sure you can hear well enough copy callsigns before transmitting. There might be occasions on SO-50 when you're the only one on, but over the 'States, this is rather rare on AO-51, especially in high power mode. We're having problems with dead carriers on AO-51 this week, where sometimes even the regulars with good antenna setups can't get in due to interference from stations without PL. Please listen first and use the correct PL. 73's and good luck! September 11 to September 18 FM Repeater, L/S Uplink: 1268.700 MHz FM, No PL Tone Downlink: 2401.200 MHz FM [ANS thanks KD6PAG, for the above information] /EX SB SAT @ AMSAT $ANS-253.05 Suitsat Re-enters AMSAT News Service Bulletin 253.05 From AMSAT HQ SILVER SPRING, MD. September 10, 2006 To All RADIO AMATEURS BID: $ANS-253.05 All, On September 7, 2006 at 16:00 GMT, SuitSat-1 re-entered about 1400 km south-southwest of Western Australia. For more details, including the winners of the Chicken Little Contest, please go to: http://www.amsat.org/amsat-new/ariss/suitsatContest.php I want to thank all who made SuitSat-1 the phenomenal event that it was. Your hard work and dedication paid off. In just 3 weeks the SuitSat team developed and delivered a safe satellite system that has gained the confidence of the international space agencies. The web and PR team were able to garner unprecedented press coverage of our ham/educational outreach activity, including over 9 million hits on www.suitsat.org in February. Students around the world had the opportunity to participate in a 7 month "school spacewalk" with the artwork, pictures, signatures and voices on-board. And the "super-sleuth" ham radio operator extraordinaires were able to pull a significant amount of data from the satellite despite of its low signal strength. And my congratulations to the students and adults who won the Chicken Little contest!! Next for SuitSat-1--the commemorative certificates/diplomas. And at the AMSAT-NA symposium/ARISS meeting we will discuss our thoughts and plans for a potential SuitSat-2. Stay tuned! 73, Frank H. Bauer, KA3HDO AMSAT V.P. for Human Spaceflight Programs ARISS International Chairman [ANS Thanks Frank Bauer, KA3HDO, for the above information] EX/ SB SAT @ AMSAT $ANS-253.06 ARISS STATUS AMSAT News Service Bulletin 253.06 From AMSAT HQ SILVER SPRING, MD. September 10, 2006 To All RADIO AMATEURS BID: $ANS-253.06 ARISS Status September 4, 2006 1. Tennessee School Contact Successful On Monday, August 28, students from Northeast Middle School in Clarksville, Tennessee had the opportunity to speak with the ISS. Jeff Williams, KD5TVQ, answered 19 questions asked by ten children via the telebridge station VK4KHZ in Australia. Jeff Williams’ niece was one of the children selected to participate in the session. A local paper covered the contact. Twenty-one connections, including 3 repeater nodes, from 7 countries were made to the EchoLink AMSAT (101 377) and JK1ZRW (277 208) servers. Audio was also fed into the IRLP Discovery Reflector 9010, and was webcast courtesy of Verizon Conferencing. The Leaf-Chronicle wrote a story on the event entitled, “Students make long-distance call to astronaut in outer space.” See: http://www.theleafchronicle.com/apps/pbcs.dll/article?AID=/20060829/NEWS01/… 2. ARRL Article on Japanese Contact ARRL covered the Sendai Yoshinari School contact in its article, “Junior High Schoolers in Japan Speak with Astronaut via Ham Radio.” See: http://www.arrl.org/news/stories/2006/09/01/3/?nc=1 3. School Contact Mentioned on Space.ref The Space.ref website has a brief entry on the Teven Tintenbar School in Australia. See paragraph 19 on: http://www.spaceref.com/news/viewsr.html?pid=21694 4. Options to Speak with Friends, Family from Space Include Ham Radio The Canadian Space Agency web site describes the options available to the ISS crew members for contacting friends and family on Earth. Ham radio is one of the options mentioned. See: http://www.space.gc.ca/asc/eng/astronauts/living_relaxing.asp 5. ARISS TIM Held The ARISS team held a Technical Interchange Meeting August 28 -31 at Goddard Space Flight Center. ARISS Delegate Sergey Samburov was able to attend the discussions which covered ARISS hardware and software, SuitSat-2 design and development, and school operations. [ANS thanks Carol, KB3LKI, for the above information] /EX In addition to regular membership, AMSAT offers membership in the President's Club. Members of the President's Club, as sustaining donors to AMSAT Project Funds, will be eligible to receive additional benefits. Application forms are available from the AMSAT Office. 73, This week's ANS Editor, Dee Interdonato, NB2F nb2f at amsat dot org _____________________________________________

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S band or any backup?
by G0MRF＠aol.com 10 Sep '06

10 Sep '06

On the subject of a parallel S band TX. That may or may not be simple depending on what else is available inside Eagle. But in any event it should not require switches. About two years ago when there was a similar period of outrage on the BB, the hot topic was the wisdom of flying an untried or tested SDX transponder without a switchable conventional 'linear' backup. I beleieve it was Bob who announced "There will be no conventional linear transponder in Eagle" I was very pleased to see Rick, W2GPS, leap quickly into the debate and reassure everyone that the complicated DSP + logic in the SDX would be backed up by conventional linear electronics. 'just in case' In a recent mail the UV transponder has been referred to as having unbelievably high audio quality. An apparent and very well justified comment on the quality of the SDX. What I can't recall seeing, is any reference to any fall back position of a linear system as a back up. It's worth remembering that 3 - 5 years time will be the peak of the sunspot cycle. High solar activity, or an unfortunate error with the orbital change burn as AO-10, could result in the satellite receiving a great deal of radiation. It would be good to know that the linear backup plans have not been quietly filed in the waste paper basket. If it hasn't, then a parallel transmitter for S or any other band is very simple to implement. Just split the IF, wire the other transmitter in parallel. 5W to an S band patch or whatever, and control it by turning the DC power line on or off. S band amplifiers no longer need to run in class A with 30% efficiencies, so an up to date class AB design would not be a large burden on the power budget. I suppose my quiet concern is not really the lack of S band, but; If the SDX or 2m TX fails, what is left in the current design to provide a service to the 90+% who will not have, or are not interested in C band? Good engineering is important, but planing for the unexpected is vital. Incidentally. It occurs to me that a disadvantage of having one major UV transponder operating 24/7 is that while that concept removes the need for complicated scheduling it will occupy 100kHz or so of the 2m band permanently which may not be totally desirable in a limited 200kHz bandwidth. Presumably with Eagle 2 and 3 under design / construction at the time of launch they will have differnt bands. - Maybe 2390 - 2400 ish Enjoying the debate David G0MRF

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S-Band Down Link P3E/Eagle
by WILLIAMS MICHAEL 10 Sep '06

10 Sep '06

One thing is certain, P3E will provide a real world test of S-band down link capability. It will then be perfectly clear if the decision to delete it from the Eagle was a wise choice. Mike K9QHO AMSAT 33589

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HT Mindset
by sco＠sco-inc.com 10 Sep '06

10 Sep '06

HTs are nice. I have been reading about the plans for Eagle and how it must serve the HT and CC&R community of hams. Thats fine, when Eagle is close to Earth HT users can work it. But when Eagle is 40,000 km out in space that is when the larger tracking antenna arrays should come into their own. That lets both camps (HTs and tracking arrays) use and enjoy the next HEO satellite. CC&R restrictions should be taken care of with new state laws like PRB-1 to allow Hams to have antennas on their property that asist in case of natural disasters and in the war with Islamic Facists. If the goal is to launch 3 HEO sats over a 13 year period that means design and build one style spaceframe then change the insides as more modern technology is developed over the time span waiting for launch. P3E seems to be using a tried and true spaceframe. Why did Eagle need to be different? If there are plans for a 2nd P3E #2 or #3 that would interest me more than Eagle #1 with unproven ideas. Let most of the experimentation take place in the ground stations, not in space (at least not until we can send a repairman to space to fix it). Can't PSK31 work thru a HEO using very small V and U band antennas for one thing? Let the digital crowd do that and let the SSB folks use their tracking arrays to work voice on V and U and yes even S band if the users want to try it (thru the future interference). Maybe by then we will be using digital voice with techniques to work thru the interference on S band. Are we just going to give up and move to a higher band everytime a few commercial users get on one of our bands? Why? It may take 13 years to design, build and launch the first Eagle. You can not launch 3 Eagles in 13 years with the way you are going now. Just a few thoughts from a ham satellite user. Les W4SCO

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S-band on Eagle
by Jim Sanford 10 Sep '06

10 Sep '06

Ladies and gentlemen: I have been reading the comments regarding the Eagle S-band downlink decision. I herewith respond to some. All along, the Eagle project has put a premium on hard science, rigorous peer review, and dispassionate analysis. All along we knew there might or would be some changes to what we've been planning. With several other issues on the move or decided, we took a few days in late June to hammer out, based on science, the transponder situation. We did multiple, independent link analyses, and all came to the same conclusion. We validated interference predictions with measurements that have been taken. The conclusion is that S-band is marginally useful as a downlink today (unusable in many locations), and by the time Eagle is launched, and through it's lifetime, will be unusable. Personally, I do not like this decision. I have S-band equipment that I was looking forward to using. Personally, I can live with this decision, and defend it to myself, let alone anyone else, because I am convinced that it is technically sound. As one of you commented this evening, AO-40 wasn't exactly a rock crusher on S-band. It worked, and adequately, at least on CW, but was not great. As I reflect on my personal AO-40 experiences, I now understand that there are 2 reasons for my disappointment. Local noise was one, and transponder distortion was another -- the latter will be corrected by SDX. S-band on AO-40, by necessity not choice, got many of us out of our comfort zones and convinced us that microwaves really aren't that hard. Let's enter the realm of S up and C down with that same realization. REMEMBER THAT AMSAT IS DEVELOPING THE GROUND STATION ALONG WITH THE SPACE SEGMENT. You will not be left on your own to develop ground equipment. You will not be asked to mortgage your house; affordability by the masses is a key component of the design for the entire system. Comparison with AO-51 is an "apples and oranges" thing. The path losses are much different. FM is very unlike CW/SSB or wideband digital modes. Remember that a goal of the Eagle system is that everything is on all the time. No more matrix switches, no more schedules. We need up and downlinks to be useful throughout the entire orbit. Why did we "regress" to U/V? For one reason, many of you asked for it, and some of us worked hard to somehow incorporate that capability in response to member's desires. The foot in the door was the utility of a V-band beacon in case everything else goes sour. The forcing function was as follows. A goal of Eagle has always been some kind of hand-held or jump bag portable ground station capability for entry into the emergency area while the tsunami waters are receeding and the hurricane winds are down to gale force. Many of us thought we could take advantage of the gain in small antennas to do this on the microwaves. Rigorous link analysis led us to the conclusion that the best place to do this is U/V -- both from a RF/DC power perspective, and from a link standpoint. This leads to the digital and "traditiona"l transponder package for U/V, implemented in SDX. Why not also include a (switchable) S-band downlink in parallel with the V-band? Remember, no switches. Also, we run into an antenna space problem. We've already increased the size of the spacecraft from where we started, and for many reasons, do NOT want to build something as large as AO-40. A couple of you have commented this evening that perusing EaglePedia has not revealed the details of the decisions. That is because, while Bob McGwier (N4HY) and I have been working on the report of the meeting, it is not public. We've been working hard on it since June, in and around other AMSAT, ham radio, and life events. Shortly after I push send on this message, I'll begin my final look at that document prior to public release. Before I go spend time with the spousal unit TONIGHT, I will finish it and publish it. I will send an announcement on the amsat-bb that it is public. To read the report, go to the EaglePedia main page, and select project index. From there, select Team and Meetings, and there will be several options, not all public. The San Diego meeting minutes will be obvious and public. Several of you have commented, "If S-band is unusable, why is it flying on P3E?" Fair question, but I can't answer for AMSAT-DL. I DO know that the P3E system design is considerably older and farther along than Eagle. Eagle design decisions were made based on the best information in June of 2006. Aspects of this discussion have been worthy of /dev/null. More aspects of this discussion have raised valid points and reasonable questions, deserving of response, which is why I've been composing this note for the last four hours or so. A few have raised the old allegation of the builders doing what they want, without regard to users needs. This is not true. While the desire to advance the state of the art (part of amateur radio's justification for existence and allocation of valuable spectrum) leads to enthusiasm and study of potentially useful new techniques, this desire had no impact on our analysis-based decisions. We started with requirements and services, and explored what would deliver. I thank all of you for your interest and support. Your Eagle team is working hard to develop a system that will serve our needs, as well as advance the state of the art. As promised, we are making decisions based on sound, peer-reviewed science, not anybody's opinions or desires. Please read the report, study the spreadsheets, download the excel file and play with it. If you can, make your own measurements and put those numbers into the spreadsheet. I think you'll understand how these decisions were reached. After contemplating the report, send me your questions. I'll either respond or forward to he who can best respond. Another fundamental tenet of the Eagle project is openness, so you have a right to a response to a rational question. Please recognize that we're volunteers too, and subject to the realities of day jobs, families, and a real life. Response may not be instantaneous. Thanks again and very 73, Jim James A. Sanford, PE Eagle Project Manager wb4gcs(a)amsat.org

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