Email Detail

HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "url": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/email/G5O2W2XAWUPSMKSJFRV7TUNXKPGOC7GR/",
    "mailinglist": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/",
    "message_id": "001801c6ef31$21657110$ab9afea9@familyroom",
    "message_id_hash": "G5O2W2XAWUPSMKSJFRV7TUNXKPGOC7GR",
    "thread": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/thread/G5O2W2XAWUPSMKSJFRV7TUNXKPGOC7GR/",
    "sender": {
        "address": "k9jkm (a) earthlink.net",
        "mailman_id": null,
        "emails": null
    },
    "sender_name": "JoAnne Maenpaa",
    "subject": "[eagle]  ARRL Letter Mentions Eagle",
    "date": "2006-10-14T01:36:11Z",
    "parent": null,
    "children": [],
    "votes": {
        "likes": 0,
        "dislikes": 0,
        "status": "neutral"
    },
    "content": "The ARRL Letter, Vol. 25, No. 41 released on October 13, 2006 mentions\nEagle.  Here is a copy of the Eagle item for those who don't get this via\nARRL channels ...\n\n--\n73 de JoAnne K9JKM\[email protected]\n\n\n==>AMSAT'S PROJECT EAGLE SATELLITE SHIFTS DIRECTION\n\nAMSAT-NA has announced it's revamping the design of its high-Earth orbit\n(HEO) Project Eagle satellite, currently in the development stages\n<http://www.amsat.org/amsat-new/eagle/>. The next generation satellite will\ntake maximum advantage of software-defined transponder (SDX) technology to\noffer a broader range of easily accessible Amateur Radio payloads. The AMSAT\nBoard of Directors okayed the Eagle upgrade plans during the 2006 AMSAT-NA\nSpace Symposium and Annual Meeting held October 6-8 in San Francisco. Eagle\nProject Manager Jim Sanford, WB4GCS, outlined the changes at his Space\nSymposium forum October 7.\n\n\"The structure which we have been presenting for several years is not going\nto meet our mission needs,\" Sanford explained. \"We have moved on to a later\nstructure.\"\n\nUnder the new plan, Sanford says, Eagle's communications payloads will\ninclude a mode U/V linear transponder for SSB, CW and other modes. A second\nSSB/CW transponder will uplink on L band (1.2 GHz) and downlink on S1 band\n(2.4 GHz). Both would be usable over 75 percent of the satellite's orbit by\nan AO-13 or AO-40-capable ground station, AMSAT says.\n\nSomething new to Amateur Radio satellites is a planned low-rate text\nmessaging system similar to cellular telephone SMS. Sanford said the\ntext-messaging capability may prove valuable for providing emergency and\ndisaster communication. It will operate in mode U/V and also will be\navailable to modest ground stations over 75 percent of Eagle's orbit.\n\nEagle will also carry an advanced communications payload (ACP). The ACP will\naccommodate voice communication using an S2 band (3.4 GHz) uplink and a C\nband (5.8 GHz) downlink via a single 60 cm dish on the ground. As an\nalternative -- for stations in those parts of the world where 3.4 GHz is\nunavailable -- Eagle will provide an additional L band uplink.\n\nThe ACP also will offer high data rate communication including the\npossibility of full-motion compressed video in S2/C mode. The same mode also\ncould support an Internet link. Ground-station antennas for Eagle may even\npass muster in neighborhoods governed by private deed covenants, conditions\nand restrictions (CC&Rs), Sanford suggested.\n\nDuring a presentation on the ACP, Matt Ettus, N2MJI, said one of the goals\nof the package is to open up the satellite to a new base of users, not just\nrestrict it to elite satellite operators and sophisticated ground stations.\nEmbracing SDR technology simplifies signal handling, he explained, because\ngoing digital is just a matter of transmitting bits up and down.\n\n\"The satellite doesn't really care what the bits mean,\" he said. The\nsatellite \"just reflects bits,\" and most policy-type issues will be handled\nby ground stations.\n\nThe satellite's signal will present one wideband downlink containing\nmultiplexed data. \"There will be room for many, many carriers in the\npassband,\" Ettus predicted. The mix of users would be apportioned among both\nlow and high-rate modes, depending on overall traffic.\n\nPlans call for electronically steering the satellite's antennas to mitigate\nthe effects of the spacecraft's spin and maximize the spacecraft's\naccessibility. In a subsequent forum, AMSAT board member and well-known\nsatellite expert Tom Clark, K3IO (ex-W3IWI) discussed some of the\nmathematics and physics that would permit steering a 37-element S band\nantenna array on Eagle.\n\n\"We would intentionally steer that pattern, so the array is always pointing\ntoward Earth,\" Clark said, regardless of spin factor. He described a system\nof interferometers to do the pointing on the basis of \"master beacon\nsignals\" uplinked from different points on Earth's surface. \"It [Eagle] will\nmeasure where they are and know where to point the beam,\" he explained.\n\nIn a presentation on applying SDR techniques to satellite transponders,\nHoward Long, G6LVB, described and demonstrated a prototype SDX board. \"This\nis the holy grail of what we've been trying to do,\" he told his audience.\nLong showed how his hand-soldered SDX could be configured to accommodate\nvarious signal strengths and types within the same passband and even to\neasily notch interfering signals quickly and flawlessly.\n\nSanford concluded his presentation by saying it's time to take the AMSAT\nboard's concrete decisions and plan, schedule and build Eagle. \"We're about\nto start spending some serous money,\" he said. During a later\nquestion-and-answer session, Sanford stressed that reliability of the\nultimate Eagle satellite is a key goal. \"I want no single-failure mission\nkills on this satellite,\" he said.\n\nProject Eagle still needs to raise $33,500 by December. Eagle could launch\nby 2010. The whole project will cost some $600,000.\n\nDuring the AMSAT-NA annual meeting October 8, President Rick Hambly, W2GPS,\nexpressed his enthusiasm for Project Eagle. \"I think it will be the greatest\nthing we've ever done!\" he said. The 2007 AMSAT Symposium and Annual Meeting\nwill take place in Pittsburgh.\n\n\n\n",
    "attachments": []
}