- Eagle (INACTIVE) - mailman.amsat.org

Suggested 2008 Efforts
by Dick Jansson-rr 10 Nov '07

10 Nov '07

Bob: While you are looking at the plans for what we need to accomplish in 2008, I think that in the RF area we should include a physical modeling of at least the key parts of Tom Clark's suggested phased array antenna. We need to prove the principle. We will need the RF amplifiers and distributed gain aspects of this antenna to meet our orbital RF power and directivity goals. This then demands the creation of some real hardware - getting us past the heise luft part of the design into something that can point us to what the all-up, on-orbit hardware should look like. If this line is not examined, we then need to have a proposal for what we should pursue..... Tom's proposal seems like a reasonable starting point. Such an project will require the efforts of a multi-technology team. '73, Dick Jansson, KD1K <mailto:kd1k@amsat.org> kd1k(a)amsat.org <mailto:kd1k@arrl.net> kd1k(a)arrl.net

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Eagle Management Change
by Jim Sanford 09 Nov '07

09 Nov '07

Team: Last night I transmitted a significant letter to Rick Hambly, Bob McGwier, and the AMSAT Board of Directors. As a result of life changing events this year, I have realized that I no longer have time for amateur radio and therefore Eagle. With GREAT regret, I tendered my resignation as Project Manager and Assistant VP (Director) of Engineering. I simply do not have the time to do this right, and would therefore prefer someone else do it. I deeply regret having to take this decision. I got into this when asked because I saw it as a chance for me to give something back to AMSAT. It also gave me the wonderful opportunity to work closely with the awesome intellect that you all represent. Working with you people, this team, has been a highlight of my personal and professional life. It is painful to step away, but I must do so -- I'm over extended, and must reprioritize some things in my life. Many of you have worked very hard and have worked hard at doing things differently. In the process, you've taught the ENTIRE ORGANIZATION some new things that we must deal with in todays era of electronics -- both process and technical details. I beg you all to not give up and please continue. I will support and encourage from the side lines, as I can. Thank you all for all that you've done. I wish you, and Eagle, only good things. Very 73, Jim wb4gcs(a)amsat.org

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Re: Eagle Management Change
by Bill Tynan 09 Nov '07

09 Nov '07

Tom: Thanks for the vote of confidence. The answer in NO, not at my stage in life. I was thinking in terms of Barry Bains - replace one retiered Navy officer with another. 73, Bill ----- Original Message ----- From: "Tom Clark, K3IO" <K3IO(a)verizon.net> To: "Bill Tynan" <btynan(a)beecreek.net> Sent: Thursday, November 08, 2007 2:39 PM Subject: Re: [eagle] Re: Eagle Management Change > Bill Tynan wrote: >> Jim: >> >> I am very sorry to learn of your resignation as Eagle Project Manager. >> Big >> programs such as Eagle, no matter what kind of organization is doing >> them, >> require the type of disciplined management you have been providing. I >> can >> think of an AMSAT project >> completed a few years back which would have benefited greatly from your >> kind of leadership. >> >> It know your work as Eagle Project Manager has been a strain, especially >> since you are also holding down a full-time job. Many AMSAT functions >> require talented people who don't have to work for a living. But such >> people >> are hard to find. >> >> I hope the AMSAT officers will be able to locate someone who can fill >> your >> shoes, but that will be difficult. >> >> Good luck and hope to see you active in AMSAT again when that becomes >> possible. >> >> 73, >> >> Bill, W3XO >> > Would you be interested? -- Tom

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FYI -- One Laptop per Child (OLPC) Opportunity
by Tom Clark, K3IO 09 Nov '07

09 Nov '07

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upcoming events
by Robert McGwier 08 Nov '07

08 Nov '07

I would like to hold a Teamspeak meeting on Monday night starting at 9 P.M. eastern time. Between now and early December I am going to be putting together a plan forward and I will be seeking input from many of you. We need to hold a meeting as soon as it is practical to hold it and we find the appropriate venue. My only mandatory attendance for this particular Teamspeak session is Bob Davis and I, so if Bob cannot make this, we will move it. Secondly, if Jim is available, I would like for him to come and give us his exit report if he wants to and for us to be able to let him hear much we want him back when he finds his busy life will allow him to return. My main agenda item for Monday night will be for us to get a report on the activities of the AMSAT lab construction delivered by AMSAT Lab director Bob Davis. Ron Bettini of Hawk Space Institute is about to deliver a request for volunteer help for some specific tasks that need doing for Hawk to finish integration of its Cubesat. I have agreed to try to advertise the need. I assume Bob will be his proxy but Ron is most welcome. AMSAT and Hawk are going to jointly administer a "space camp" at UMES next summer if the details can be worked out (we stop talking and start acting) and we are rapidly approaching the time when the teachers we are trying to attract will have already made application to others and committed their available funds. We are going to need to volunteer adjunct faculty from our engineering team to aid with this. AMSAT is going to join with Hawk in a balloon project at the "spend a few dollars and package the Suitsat hardware for the balloon" level. I would like for Bob to fill us in on those details. I want to get together as soon as possible a clear set of parameters for the RF systems I intend to have us build during 2008 and for which the AMSAT BOD has given us a budget. I am not looking to build flight hardware but a significant investment has been made in prototyping tools so we can develop code for the full up HELAPS and the ACP software foundations on the same development platform. We need to put together a clear concept of our intended operations on Intelsat and to get some prototype hardware built so the prototype development system can put it all on the air and demonstrated and tested. As soon as is practical, we need to be able to demonstrate a prototype ACP and a prototype SDX so we show the functionality can be built if funding is found for the flight system and the launch. We have not yet reached the point where any firm decisions can be made which would allow us to build fight RF hardware for either Eagle or Rideshare because they are significantly different missions. One is RF with a few space challenges and with more DC power than we ever dreamed possible. The other is all the challenges of managing a complex satellite on which we grudgingly allow what RF can be accomodated. But I have my marching orders from my boss, BUILD SOMETHING. I am prepared to demonstrate we can. By the time I get done writing all of that up for the journal Engineering Notebook column, my arms will be breaking off. Should we have other agenda items that need to be covered, please email me directly. The bod and officers outside the Eagle team members are NOT invited to this session because this has nothing to do with tech snobbery. There is a limit to the number of people we can get on there. We have never reached it and I don't want to try and I want to try to stay focused on the long reports I have requested. I am seeking your input on things you would like to see us to discuss. You will be able to listen to the entire session should you so desire afterwards and we finish transcoding it and putting it up for download. There will be a written report posted to Eaglepedia as soon as I figure out the levers to pull. Bob -- AMSAT Director and VP Engineering. Member: ARRL, AMSAT-DL, TAPR, Packrats, NJQRP, QRP ARCI, QCWA, FRC. ARRL SDR WG Chair “An optimist may see a light where there is none, but why must the pessimist always run to blow it out?” Descartes

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TS Meeting
by Dick Jansson-rr 08 Nov '07

08 Nov '07

Bob: I will be available for the TeamSpeak meeting on Monday 12.11.07 @ 2100est. Dick Jansson, KD1K <mailto:kd1k@amsat.org> kd1k(a)amsat.org <mailto:kd1k@arrl.net> kd1k(a)arrl.net

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Phased Array on an IC
by Tom Clark, K3IO 07 Nov '07

07 Nov '07

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Phase 4 on Amateur Radio Newsline
by JoAnne Maenpaa 02 Nov '07

02 Nov '07

Hi Everyone, In case you haven't seen it, here is the pre-feed version for Amateur Radio NewslineT Report 1577 - November 2, 2007 in regard to Phase 4 Lite. -- 73 de JoAnne K9JKM k9jkm(a)amsat.org HAM RADIO IN SPACE: AMSAT SAYS HAM RADIO GEOSAT IN PLANNING Its called Phase 4 Lite and it will likely change the face of ham radio forever. Amateur Radio Newsline's Bruce Tennant, K6PZW, has a peek at the future of a geosynchronous ham radio satellite in Earth orbit: -- The weekend of October 26th to the 28th has likely changed the face of ham radio space operations. So say two leaders in the Amateur Radio space program speaking at the AMSAT-North America Space Symposium in Pittsburgh, Pennsylvania. That's they announced that a first-ever geosynchronous ham radio satellite is now in its initial planning. In satellite talk, geosynchronous means stationary in the sky. From the standpoint of a ground station user, it means always knowing where to point an antenna. No tracking and no guesswork. At that gathering, AMSAT President Rick Hambly, W2GPS, and Vice-President of Engineering Bob McGwier,N4HY, announced that AMSAT has been in consultation with Intelsat. This, regarding an application of an Intelsat platform carrying amateur radio satellites into geosynchronous orbit. The Phase IV Lite Geosynchronous Payload is planned to consist of similar transponders already under development for the Phase 3 satellites. Accelerated development on the digital Advanced Communication Package is anticipated. The Intelsat geosynchronous platform would be able to provide the AMSAT Phase IV Lite payload with approximately 400 watts of DC power for 15 years. In addition to the on-orbit payload AMSAT plans to develop an earth station attainable by the average ham so that users can immediately take advantage of the audio, digital messaging, and video services of the Phase IV bird. The Advanced Communication Package would be a self-contained earth station which could be sent with amateur radio communication teams or delivered to disaster areas to provide for 24 hour a day, 7 day a week and 3565 days a year emergency communications. These teams would be able to point a small dish at a predictable spot in the sky and immediately begin delivering disaster communication support without depending on the vagaries of High Frequency propagation. But that's not all. Hambly and Mc Gwier say that the Phase IV payload could also be used to provide a Tracking and Data Relay System Satellite -like relay of ARISS communications. The current 10 minute school contact could now be expanded to hours-long contact with the International Space Station. This opens possibilities for extended student involvement with experiments aboard the space station. As the late Roy Neal, K6DUE, might have said: Truly a new world of Amateur Radio. For the Amateur Radio Newsline I'm Bruce Tennant, K6PZW, in Los Angeles. -- So when can we expect this new satellite to be on-orbit?, AMSAT says that engineering studies, funding studies, among other negotiations are continuing so no specific date can be set. However Bob McGuier N4HY observes that the project is far enough along that AMSAT needs to begin planning engineering work and possible construction of such a geosynchronous payload so it is ready if Intelsat says they have a ride for it. (AMSAT-NA)

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Re: New Module
by Dick Jansson-rr 01 Nov '07

01 Nov '07

Chuck: Implicitly all that information existed already on the E05 60 Module drawing. I have today changed this drawing to Rev.02 to incorporate these specific dimensions. You have 28.4mm clearance to the cover flange of the E05 62 Connector Plate, which is intruded by 3.2mm for the cover screw and its PEM nut pressed into the flange. All other dimensions that you need are located on the several drawings, which is why I uploaded the complete set of drawings. '73, Dick Jansson, KD1K <mailto:kd1k@amsat.org> kd1k(a)amsat.org <mailto:kd1k@arrl.net> kd1k(a)arrl.net -----Original Message----- From: Chuck Green [mailto:greencl@mindspring.com] Sent: Thursday, 01 November, 2007 16.21 To: Dick Jansson-rr Cc: Bob Davis Subject: Re: [eagle] New Module Hi Dick, For those who have extreme connector issues it might be helpful if they had information regarding the cover attachment to the connector plate. This information might logically be added to the connector plate drawing. How far does the nut protrude into the module area? What is it's diameter? What is the distance from the top of the PCB to the center of this nut (assuming 0.062 inch PCB)? And how far might the screw reasonably be expected to protrude into the module area? Thanks, Chuck Dick Jansson-rr wrote: > > Bob: > > I have uploaded the drawings for the new E05 60, 140x180 Module, to > Eaglepedia. I did this so that people so interested can go there and > look at these drawings. > > I plan shortly, however, to modify the PCB and Baseplate slightly by > adding more mounting screws. I have somehow to convey that some of the > added screws are optional depending upon the PCB dissipation. This > step to add more screws is part of the realization that screws spaced > 50+mm apart may not provide sufficiently effective contact of the PCB > to the Baseplate. Modules such as the U Receiver will definitely need > the added screws. This tradeoff on this module is a significant > reduction in the need for added heat sinks, and their attaching screws > in the middle of the PCB. > > Your timely comments on this module would be appreciated. > > '73, > > Dick Jansson, KD1K > > kd1k(a)amsat.org <mailto:kd1k@amsat.org> > > kd1k(a)arrl.net <mailto:kd1k@arrl.net>

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New Module
by Dick Jansson-rr 01 Nov '07

01 Nov '07

Bob: I have uploaded the drawings for the new E05 60, 140x180 Module, to Eaglepedia. I did this so that people so interested can go there and look at these drawings. I plan shortly, however, to modify the PCB and Baseplate slightly by adding more mounting screws. I have somehow to convey that some of the added screws are optional depending upon the PCB dissipation. This step to add more screws is part of the realization that screws spaced 50+mm apart may not provide sufficiently effective contact of the PCB to the Baseplate. Modules such as the U Receiver will definitely need the added screws. This tradeoff on this module is a significant reduction in the need for added heat sinks, and their attaching screws in the middle of the PCB. Your timely comments on this module would be appreciated. '73, Dick Jansson, KD1K <mailto:kd1k@amsat.org> kd1k(a)amsat.org <mailto:kd1k@arrl.net> kd1k(a)arrl.net

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Call for Symposium Photos
by JoAnne Maenpaa 31 Oct '07

31 Oct '07

Hi everyone, I'd appreciate it if you could forward me any photos from the Symposium that you think would be suitable to print in the AMSAT Journal. I noticed a few nice cameras clicking away :-) Direct e-mail to me is k9jkm(a)comcast.net in case the amsat alias gives you any heartburn with big attachments. Thanks! -- 73 de JoAnne K9JKM k9jkm(a)amsat.org

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Engineering titles
by Robert McGwier 30 Oct '07

30 Oct '07

I was not aware, though I should have been, that Rick enacted an org chart through the BOD before I "returned from the dead". Anyone I have been calling AVP Eng. (Bob Davis, Jim Sanford, and Lou McFadin) are now engineering directors. I like it better myself now that I think about it more carefully. I just wanted to be prickly and argue about it for the sake of arguing since it is different from what was done before I went into the cold! Bob -- AMSAT Director and VP Engineering. Member: ARRL, AMSAT-DL, TAPR, Packrats, NJQRP, QRP ARCI, QCWA, FRC. ARRL SDR WG Chair “An optimist may see a light where there is none, but why must the pessimist always run to blow it out?” Descartes

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Some need changes
by Robert McGwier 29 Oct '07

29 Oct '07

Eagle team members: Bob Davis, Jim Sanford, and I met in Pittsburgh as the engineering executive team and we made some changes. Bob and Jim are Asst. VP Engineering and continue to remain in those offices until such time as they do not wish to hold them or another AMSAT opportunity interests them. The office of project manager does not exist as of the annual meeting. I do NOT want this read the wrong way. There are some delicate negotiations that are about to take place with multiple entities. For all sorts of reasons, none of them having a single solitary thing to do with ego, performance, etc. require the person speaking on behalf of the project, for its budget, and direction must reside in the VPE. As of the annual meeting and the budget passed by the AMSAT BOD, the only projects receiving funds in 2008 are RF payloads, antennas, SDX, ACP, and the Eagle structure. The Eagle structure is going forward because it serves multiple purposes. No funds will be expended on any of those systems that are unique to Phase 3 satellite systems since our goal, to put RF payloads on Intelsat, does not need solar panels, attitude sensors, attitude control mechanisms, etc. We are going to need to hold some meetings soon. I will call for them shortly. As much as some of you disliked either the tone or approach of functional requirements and specifications, we are without choices now. We are going to have to talk to and work with some fairly serious engineering firms or offices about getting payloads built that will last for 15 years. We cannot do less than this and expect anyone to give us the millions of dollars this program is going to take. That said, I believe we can raise this money. Expect more to follow shortly. Bob -- AMSAT Director and VP Engineering. Member: ARRL, AMSAT-DL, TAPR, Packrats, NJQRP, QRP ARCI, QCWA, FRC. ARRL SDR WG Chair “An optimist may see a light where there is none, but why must the pessimist always run to blow it out?” Descartes

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Interfacing to CAN-Do Widgets - Updated User's Guide
by Stephen Moraco 28 Oct '07

28 Oct '07

Hi all, I've updated our CAN-Do project web-site with new content See: http://can-do.moraco.info/ Various top-level pages which you navigate to using the links along left column have "<- New" marks in yellow to denote the updates. Of particular interest is the new material found linked from our reference page. Designing a Module or Payload which uses a CAN-Do widget? ----------------------------------------------------------------------------------------- You will want to make sure you have reviewed the updated Widget User's guide I've posted for review (linked from the reference page.) See the revision history in the guide for what's new. If you would like to see corrections made, or additional material added please let me know. Regards, Stephen, KZ0Q -- kz0q(a)amsat.org (formerly kc0ftq)

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Phased Array Concepts
by Tom Clark, K3IO 26 Oct '07

26 Oct '07

I have (finally!) put the finishing touches on my magnum opus describing my ideas on phased arrays and shipped it off to be included in the Pittsburgh symposium proceedings. If you want to see it, it is available for viewing at http://mysite.verizon.net/w3iwi/electronic_scanning_antennas.pdf. This version has some figures in color, but the proceedings is in B&W (this format is available if you need it). This took me a lot longer than I anticipated. I had a couple of fairly major Gates-induced computer failures, some of which still plague me (like I'm using my notebook for all Email). I advise against the use of Office 2007. I am hoping that this week I will have time to test Dan's hardware so I can have some results to report by Pittsburgh. Matt -- this has the numbers I was trying to remember last weekend. For all -- your comments and critiques are solicited. 73, Tom

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Symposium presentations
by Jim Sanford 25 Oct '07

25 Oct '07

All: I have the display computer which will be used to show presentations during symposium. If you can, please get them to me early. I can accommodate a "stick", CD, or DVD. I'll be in the BOD meeting and "around"today and tomorrow. I can be reached at my cell, 757 869 7892. 73, Jim wb4gcs(a)amsat.org

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More Information
by Dick Jansson-rr 23 Oct '07

23 Oct '07

John: This will be my concluding note on this subject prior to the Symposium. I have tuned the analyses done yesterday and that data follows. For a single 1.4mil ground plane with a single IC located 52mm from the Baseplate edge, a 1.0W dissipation results in a temperature rise of 38.2°C For a double 1.4mil ground plane with a single IC located 28mm from the Baseplate edge, a 1.0W dissipation results in a temperature rise of 21.1°C. For a double 1.4mil ground plane with TWO ICs, spaced 40mm and both located 28mm from the Baseplate edge, a 1.0W dissipation in each IC results in temperature rises of 26.1°C (one at 26.0 and the other at 26.2). Total dissipation here is 2.0W. In other words, doubling the ICs, with this spacing, only added ~24% to the temperature rise. This shows you how this module design handles the kind of power situations that you have in the URx. See you in Pittsburgh? 73, Dick Jansson, KD1K <mailto:kd1k@amsat.org> kd1k(a)amsat.org <mailto:kd1k@arrl.net> kd1k(a)arrl.net

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New Data
by Dick Jansson-rr 20 Oct '07

20 Oct '07

John: I have just completed some analytic evaluation of the clamping of the PCB generously to the side edge of the Baseplate, as in the revised design shown to you on the E05 60 Module, its new designation. The model consists of a 80x80mm PCB, with 72x80mm freely hanging away from the Baseplate. One model uses only a single 1.4mil copper ground plane layer and has the IC mounted 52mm from the clamped PCB to the Baseplate. The second model uses a dual 1.4mil copper ground plane and has the IC mounted 20mm from the clamped PCB to the Baseplate. I ran a series of four power levels in the IC, 0.25W, 0.50W, 0.75W, and 1.00W. The IC temperatures are fairly linear with power for each case. In the first case with the IC mounted pretty far away, 1.00W of power caused a temperature rise of 38.4°C above a 20°C Baseplate and enclosure. For the more closely mounted IC, the temperature rise for the 1.00W case is 28.6°C above the 20°C of the Baseplate. You can detect that the temperature rise does not seem to be very linear with the distance from the Baseplate. As this data is still quite new for me, I do not have an explanation for this effect. I did, however, want to make you aware of the data so that you can start to plan to see what you can do in the URx redesign. I plan to do some variations on these two cases to try to understand the processes more completely. I do, however, have to wrap up this data process so that I can complete my presentation in Pittsburgh. I hope that this information will be of use to you. 73, Dick Jansson, KD1K <mailto:kd1k@amsat.org> kd1k(a)amsat.org <mailto:kd1k@arrl.net> kd1k(a)arrl.net

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Review
by Dick Jansson-rr 19 Oct '07

19 Oct '07

Bob: Attached is drawing E05 64, 140x180 PCB. This is being sent out for your review, prior to being posted on Eaglepedia. This PCB gives more working area with fewer interruptions to the working area (just essentially two posts). Please look at this and forward any corrective comments. '73, Dick Jansson, KD1K <mailto:kd1k@amsat.org> kd1k(a)amsat.org <mailto:kd1k@arrl.net> kd1k(a)arrl.net

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Revised Module Suggestion
by Dick Jansson-rr 19 Oct '07

19 Oct '07

Bob: Shown in this message is a picture of the revised module design that you and I have been working on in the last few days. The revised cover has not yet been done but its features are implicated in this current view. The machined base plate has robust beams around three sides. Further, there are stiffening beams machined on the bottom side of the baseplate. The side to side dimension of the baseplate is shown at 141mm, reduced from its previous 147mm. This step was needed to accommodate the cover screw heads now on the side of the module. Shown also is a revised connector plate, which is increased in width from the previous 122mm to the 141mm of the baseplate. This should ease the connector space issue a little as the cover PEM nuts have accordingly been moved out leaving a 125mm wide clear space for connector activity, an increase from 106mm. The PCB is unchanged, however its standoff posts are now 6.4mm (1/4 inch) from the previous 4.8mm (3/16 inch), a step needed for connector plate screws. The cover will slide over the assembly shown and it will have only one flange, along the rear side. The long sides will use screws placed into the edges of the assembly (formerly a flanged side). This means that there will not be mechanical loading on the baseplate caused by irregular flange bends, as in the present cover design. Regarding this design of module, the PCB access has been fully maintained, but the cover cannot be removed while the module is installed into the spacecraft, a feature that had been planned with the current design. Discussion is invited. Dick Jansson, KD1K <mailto:kd1k@amsat.org> kd1k(a)amsat.org <mailto:kd1k@arrl.net> kd1k(a)arrl.net 125x180 Module Assembly.jpg

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Still Even Another Revision
by Dick Jansson-rr 19 Oct '07

19 Oct '07

Bob: Owing to the "popularity" of these discussion, I have done further revisions of the E05 20 Module. It is now officially termed a "140x180" module as the PCB has grown to that size. The size increase has allowed an increase in PCB working area to a clear 126x173.6mm, 6.35mm deep, save for three protrusions - two support posts and the third at the front to accommodate the third connector plate screw (this later post is not in contact with the PCB as explained earlier). The three attached PDF files show the module with its cover attached, cover removed and PCB and cover removed. I shall shortly be able to issue a drawing of this revised PCB. The cover has further been simplified as the rear mounting flange has been removed and replaced by side-inserted screws, as is for the cover's sides. Chuck has properly noted that such a mounting of the PCB will enhance the thermal characteristics of the PCB. I plan to combine an earlier PCB thermal analysis and this new PCB configuration and expect to be able to identify the power handling capability of this PCB without the use of any added heat sinks. The enhancement should certainly be available along three sides of the PCB. That data should be available for the Symposium. Dick Jansson, KD1K <mailto:kd1k@amsat.org> kd1k(a)amsat.org <mailto:kd1k@arrl.net> kd1k(a)arrl.net

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Updated Module
by Dick Jansson-rr 18 Oct '07

18 Oct '07

Bob: In response so some of Chuck's, Juan's and other's suggestion, I have updated the 125x180 module to incorporate integrally machined support posts and revised the cover attachment to the connector plate. While making this change permanently attaches the posts to the baseplate, it also means that there is no flexibility in omitting any posts. For Chuck's information the nomenclature of the module is the PCB size, as it has been for seven years. There may possibly be PCBs that would be 75mm larger, totaling to be a 200x180mm PCB, but I certainly would not expect anything larger than that. Also note that the depth of the cavity below the posts is 6.35mm, save for in the very center where there is an attachment for the connector plate that is located 0.75mm below the PCB for a space in the center that is 10mm wide by 6mm deep from the connector plate. I was loathe to locate such a piece here but felt the need for a third attachment for the connector plate. For Juan, the use of socket heat cap screws is not out of the question, I just did not replace them in this assembly at this time. For John, I will have to create a revised footprint of the baseplate interface to the bottom of the PCB, which obviously is not quite as limited as just some 0.250inch cylindrical posts. I kept the basic pad of that same general size, but the machining aspects of things get in the way of keeping it quite to the same exact area of spots. Bob Davis and I discussed extensively the issue of being able to remove the cover while the module is mounted in the spacecraft. To achieve a relief in the issue of the cover dictating the shape of the baseplate, instead of the converse, this feature had to be sacrificed. I well remember the discussions of earlier this century, but the issues that Juan raised seemed to overpower the need to remove the cover while still in the spacecraft. To accommodate the side-mounted screws the sides of the module were "pulled in" by 3mm on each side, with the finished module now being 141mm plus 2x0.5mm for the cover (=142mm) and plus screw heads, instead of the former 147mm overall. (Now don't get bent all out of shape on that fuzzy math. No comments thereof will be accepted.) The module mounting pitch is 150mm leaving 8mm between adjacent modules for two sets of screw heads. One type of module will, however, have to retain its removable cover feature, however, and that for the power modules as the heat sink screws must be accessed in order to mount the module into the spacecraft. What this design is to look like has not been redetermined at this point. Dick Jansson, KD1K <mailto:kd1k@amsat.org> kd1k(a)amsat.org <mailto:kd1k@arrl.net> kd1k(a)arrl.net

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125x180 Module Assembly
by Dick Jansson-rr 17 Oct '07

17 Oct '07

Bob: Attached are three pdf views of the proposed revised Eagle module, and open view, fully closed view, and a view w/o the PCB. It has been a lengthy day getting all of the darned 0.5mm cover bends correct and holes properly placed for full mating of the cover with the baseplate (such things as 0.581mm hole placement discrepancies - ugh!). If built from the drawings that can be made from these objects, there should be a good fit in the real hardware. I do not presume as to what the "real" next step wants to be, as I do not propose to make the 2D drawings until the discussions have settled down to agree that this is what we collectively like, or at least collectively accept. Please advise. '73, Dick Jansson, KD1K <mailto:kd1k@amsat.org> kd1k(a)amsat.org <mailto:kd1k@arrl.net> kd1k(a)arrl.net

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[Fwd: Re: [Fwd: [Eagle] SANFORD quicklook comments on Eagle Module Mechanical Requirements]]
by Jim Sanford 14 Oct '07

14 Oct '07

All: Thanks to the efforts of Dave Hartzell, we have a page on EaglePedia for the entry and response to peer review comments on the new module design. Please post your comments at: http://www.amsat.org/amsat-new/eagle/EaglePedia/index.php/Module_Requiremen… Bob, The form allows for your responses there as well. Thanks & 73, Jim wb4gcs(a)amsat.org -------- Original Message -------- Subject: Re: [Fwd: [Eagle] SANFORD quicklook comments on Eagle Module Mechanical Requirements] Date: Wed, 10 Oct 2007 22:46:35 -0700 From: Dave hartzell <hartzell(a)gmail.com> To: Jim Sanford <wb4gcs(a)amsat.org> References: <470AF037.6020008(a)amsat.org> Jim, Take a look at this at let me know. its not a table, per se, but it is the same format that we used for the 70cm RX test plan comments... http://www.amsat.org/amsat-new/eagle/EaglePedia/index.php/Module_Requiremen… Dave On 10/8/07, *Jim Sanford* < wb4gcs(a)amsat.org <mailto:wb4gcs@amsat.org>> wrote: Dave: I'd like to create a page like the U-RX page for this stuff. Couldn't figure out how to create a noew page; can you? I'd like it to be reachable both from Requirements and from Mechanical categories. On that page, I'd like a link to a table where people can EASILY enter their comments, and then Bob can EASILY enter his resolution thereof. Can you do this for us? I tried & failed. (Dick Jansson also sent comments that I'd like to get included) Thanks & 73, jim wb4gcs(a)amsat.org <mailto:wb4gcs@amsat.org> -------- Original Message -------- Subject: [Eagle] SANFORD quicklook comments on Eagle Module Mechanical Requirements Date: Mon, 08 Oct 2007 23:00:01 -0400 From: Jim Sanford <wb4gcs(a)amsat.org> <mailto:wb4gcs@amsat.org> To: Robert Davis <bob2leo(a)gmail.com> <mailto:bob2leo@gmail.com> CC: Bob McGwier <n4hy(a)amsat.org> <mailto:n4hy@amsat.org>, "John B. Stephensen" <kd6ozh(a)comcast.net> <mailto:kd6ozh@comcast.net>, Juan Rivera <juan-rivera(a)sbcglobal.net> <mailto:juan-rivera@sbcglobal.net>, Dick Jansson-rr <rjansson(a)cfl.rr.com> <mailto:rjansson@cfl.rr.com>, Jim Sanford <wb4gcs(a)amsat.org> <mailto:wb4gcs@amsat.org> References: <23536a8a0710081216r52673a0dye7945e5d4e79327e(a)mail.gmail.com> <mailto:23536a8a0710081216r52673a0dye7945e5d4e79327e@mail.gmail.com> <23536a8a0710081218q5dfd914n2ee77d5f9c924fb1(a)mail.gmail.com> <mailto:23536a8a0710081218q5dfd914n2ee77d5f9c924fb1@mail.gmail.com> All: Comments from my first quick look: 1. There are many references cited herein. It may be useful to collect these in a single section titled "References" to which you can than refer. 2. 6.5: cites machining requirements using MKS units. A year or two ago, there was an intense discussion about this on the Eagle list, with many complaining that CNC machines want inches and feet. At that time, a proposal was made that DESIGNERS be responsible for specifying both MKS and inches/feet, so that any machinist could fabricate. Request consider making this a requirement. 3. 6.6: Can we include a link to the reference? 4. 6.10: I don't understand what this is demanding, particularly the interior chip piece of it. While the need to prevent chips inside is obvious, it would appear that there is more to this story than is obvious. Please explain to me, and consider elaborating the requirement. 5. 6.11: Requests "consideration" of certain factors. This is vague and unenforceable. Please explicitly state requirements which must be met and "features" which are desireable. 6. 7.4: Uses the word "generic" but generic WHAT? It appears that a word or words are missing. 7. 7.5 et seq: What does "TBC" mean?? 8. 7.7: If possible, please include a link to the references. This is valuable information which many should read, and might, if they can get to it easily. You've obviously done a lot of homework, please share. 9. 7.8: Please elaborate on what is intended by requiring "access" for assembly. It is not clear to me what I must do if I am building one of these things. 10. 7.9: This looks good, but I have one question: Is this requirement consistent with what Juan Rivera found as a requirement for board stiffness with SMD devices? If so, please state the reason/reference. IF there's a discrepancy, let's get it resolved and publish a common requirement. 11. 7.10: What is "arbitrary stiffness"???? 12. 7.12 and 7.13: Should we consider flexibility at one end? Rationale: Boilers and steam generators which are exposed to temperatures ranging from 70F to 950F are rigidly mounted at one end, and have "sliding feet" at the other, which allows for thermal expansion. In our application, should we consider rigidly mounting one end of the PCB and allowing the other to move a bit, to prevent stress buildup which will manifest itself as a bending moment on the PCB, breaking SMD components? I'm open to better ideas, but based on what Juan has reported regarding stresses and bending of boards, this seems like a reasonable idea, given the temperature ranges our boards and enclosures might see. 13. 8.4: Please define the "standard bolting pattern." 14. 9.1: Please devine "TML" and "CVCM". 15. 9.2, 9.3: Please provide links to the references. 16. 9.5: This requirement is ambiguous. Please elaborate on what is meant by "solutions." I see the examples, but still don't understand what I must do if I'm a provider. 17. 9.7 & 9.9: Please define "MS" and "FS". 18. 9.10: Please define "GEVS" and "ASD". 19. Figure 3: Please define "G2/Hz". Hz is understandable, but what is "G2", and what is the significance of normalizing it to Hz? 20. 10.4: This appears excessively restrictive. What is magic about the dimensions provided? Is this assuming a 1, 2, or 4-layer board? Is this assuming a particular dielectric? what happens if a microwave circuit requires an exotic dielectric and a thinner material to control impedances and losses. Please provide a rationale for being so restrictive, or provide guidelines to allow variation in materials and thickness based on board functions. 21. 10.7: Please explain the rationale for not allowing components on the side opposite the connector face. (Prohibiting mounting on the lid is fairly obvious, the back wall is not.) 22. 10.8: Please explain the reason for the 12.55 mm requirement. 23. 10.10: This appears to indicate rigid mounting of connectors at one end of the module and also to the board. What will we do to eliminate stress to components and the board from temperature change? Bob, this is very good work, and the above is merely questions. Tomorrow night, I'll attempt to create in EaglePedia a page for this and a table like for the UHF RX where comments, commentor, and resolution can all be consolidated in one location. Thank you for all your hard work. 73, Jim wb4gcs(a)amsat.org <mailto:wb4gcs@amsat.org> Robert Davis wrote: > I'm specifically hoping for comments from this group. > Thanks, > bob > > ---------- Forwarded message ---------- > From: *Robert Davis* <bob2leo(a)gmail.com <mailto:bob2leo@gmail.com>> > Date: Oct 8, 2007 3:16 PM > Subject: New doc: Eagle Module Mechanical Requirements > To: AMSAT Eagle <Eagle(a)amsat.org <mailto:Eagle@amsat.org>> > > > All, > I've posted an initial draft of requirements for Eagle module > mechanical design. Looking for comments. Be gentle since it's my > frist crack at it and there's TBDs. > > http://www.amsat.org/amsat-new/eI > dontagle/EaglePedia/uploads/6/6f/Eagle_Module_Mechanical_Requirements_Oct_8_07.pdf > <http://www.amsat.org/amsat-new/eagle/EaglePedia/uploads/6/6f/Eagle_Module_M…> > > Thanks, > bob > Robert Davis > KF4KSS -- "It is far better to grasp the Universe as it really is than to persist in delusion, however satisfying and reassuring." - Carl Sagan.

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Internet issue
by Robert McGwier 09 Oct '07

09 Oct '07

Today is the day Verizon comes and I get trapped into their monopoly (FIOS). I have given up on getting Comcast to fix things or reduce their prices. With Verizon I have 3 digital boxes, faster internet, more channels of nothing on, and it all costs me $45 a month LESS than comcast. After they get the majority of us trapped in their monopoly, I am expecting the prices to rise but $45 is a ways to go. It will ultimately result in Comcast dropping their price. Anyway, enough soap box: Later today the internet switch over will occur. It may OR MAY NOT go smoothly. If it does, I will be on the teamspeak conference. If it does not go smoothly, I will not. I would suggest that we could use the Meet Me line (it is Tuesday) but when my cable goes out, so does my phone. That is the nature of a monopoly is it not? Bob -- AMSAT Director and VP Engineering. Member: ARRL, AMSAT-DL, TAPR, Packrats, NJQRP, QRP ARCI, QCWA, FRC. ARRL SDR WG Chair “An optimist may see a light where there is none, but why must the pessimist always run to blow it out?” Descartes

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progress
by Jim Sanford 08 Oct '07

08 Oct '07

Team: I'm glad to see the recent work on mechanical design of hardware modules and the phased array concepts. Thanks, Bob, Tom, and to Matt for the pointer on a good linux simulation tool. I'll get it and play this weekend when I get back in tosn. Tomorrow night is TeamSpeak. I'd like to hear more about this work from Tom, Matt, & Bob. Last item on my agenda is status and preparations for demonstration at Symposium. Thanks & 73, Jim wb4gcs(a)amsat.org

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Module Requirements
by Dick Jansson-rr 08 Oct '07

08 Oct '07

Bob: Here are my first comments regarding your Eagle Module Requirements document. These are first brush and I reserve the right to add to them. J 1) ¶6.8: I would suggest restricting the drawing sizes to A and B, as we did for AO-40, as it allows the use of easily available reproduction machinery, both in creation and replication, and in the standardization of the handling of the drawings. 2) ¶6.10: I would suggest that the term hardware elements (screws)... be used instead of ...hardware joints This more specific reference makes clear that requirement. 3) ¶7.4: You speak of generic, generic what is your reference? 4) ¶7.10: What is meant here? 5) ¶8.5: To accommodate a maximization of the spaceframe Izz, I found that I had to move the equipment panels outward as far as possible to be able to achieve this needed Izz. This step removed a lot of otherwise vacant space above the modules, thus restricting the over height of the modules, which would probably preclude the stacking of modules. Further, I dont feel that the AO-40 stacking experience was all that good. On the thermal arena and stacking, stacked modules do not radiate their heat very well and such stacking would be somewhat thermally restrictive. 6) ¶9.9: Good! 7) You have made no provision for the creation of a heat sink module that will be necessary for the really high power modules, defined hereby as greater than 5+ Watts for a 125x180 module. Also the inclusion of small heat sinks, as done for the recent URx work, does not seem to have a home in your document. I hope that these comments will help you and others. 73, Dick Jansson, KD1K <mailto:kd1k@amsat.org> kd1k(a)amsat.org <mailto:kd1k@arrl.net> kd1k(a)arrl.net

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New doc: Eagle Module Mechanical Requirements
by Robert Davis 08 Oct '07

08 Oct '07

All, I've posted an initial draft of requirements for Eagle module mechanical design. Looking for comments. Be gentle since it's my frist crack at it and there's TBDs. http://www.amsat.org/amsat-new/eagle/EaglePedia/uploads/6/6f/Eagle_Module_M… Thanks, bob Robert Davis KF4KSS

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70 cm Receiver on external reference
by Juan Rivera 19 Sep '07

19 Sep '07

Bob, Before our minor crisis I think I owed you a .wav file of the receiver. I set up as follows: * RF Input: 435.000 from HP 8662A on GSP external reference * 70 cm Receiver: Also on 10 MHz GPS external reference * IF out: to SDR-IQ I demodulated the receiver in CW mode and recorded the wav file using the SDR-IQ SpectraVue program. I can also send you an RF wav file that you can use with a new SpectraVue application that they have on their web. The file is attached. This screen shot shows the IF output on 10.700 MHz (in green) and the CW detector shape in orange with the red bar at the top showing the passband. Will this work for you? 73, Juan - WA6HTP

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YAHOO!!!! IT WORKS!!!!
by Juan Rivera 18 Sep '07

18 Sep '07

All, We need to take up a collection to buy Stephen a large hero badge. He fixed the problem and the receiver is now sitting on my bench happily receiving a signal. The new CAN-Do module that he sent me had a different address than the old one and the old files were addressing the initialization instructions to a non-existent device. All we have to do is change the address field in the initialization files and everything is fine. Whew! The train of life in back on the tracks! 73 to all, Juan

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Re: I need another CAN-Do Module
by Robert McGwier 16 Sep '07

16 Sep '07

Juan: I talked with Stephen. He is testing your replacement module. He and I both feel that the likelihood you have a faulty one is low but that there is no harm in testing this since it does turn out to be the module, it will prevent you from having to dig into the RX. Now let us suppose you receive the widget and you cannot get the PLL's to function. To what extent does the receiver function now? Does it function well enough to demonstrate at the annual meeting? If so, why not do non destructive testing if at all possible and try to get it to run before we give up completely on it. Bob -- AMSAT Director and VP Engineering. Member: ARRL, AMSAT-DL, TAPR, Packrats, NJQRP, QRP ARCI, QCWA, FRC. ARRL SDR WG Chair "If you're going to be crazy, you have to get paid for it or else you're going to be locked up." Hunter S. Thompson

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Re: 70 cm receiver inoperative with new CAN-Do module - More
by Juan Rivera 16 Sep '07

16 Sep '07

Stephen, All of the receiver power supplies are functional. My setup has not changed for a long time. I'm using the same cable harness and power supply as always. Communications are via a USB port, to a USB-to-serial dongle, to the CAN232, to the CAN-Do module. This has not changed since day-1. The CAN-Do Net Controller Software is the same installation I've been running successfully for months. It appears to run as before. It finds the CAN232 immediately and then finds your module when I click the Query button. I set the timing for 200 mSec and select a .can initialization file by clicking "Playback Log". I can then load the initialization data by clicking "heartbeat". The data appears to load at the normal rate I'm used to seeing. After loading the file there are no entries in the error log. The only odd behavior is that I can always crash the application by selecting the waterfall log after the data has been initialized. The log appears to be empty when the application crashes. If I select that log BEFORE I load the file it comes up with no problem. I've tried loading different versions of the init file (I have about 10 for various frequencies and either internal or external reference) and they all result in both PLLs failing to initialize and a dead receiver. Yesterday we stepped through the I/O lines one at a time using a DMM and toggling them using the GUI controls. They all appeared to be OK after some confusion initially. I can also toggle the power on and off although I'm bypassing it and feeding the receiver directly from the power supply. The first LO is drifting around at 598 MHz. The second LO appears to be putting out RF at 126.4 and 253.2 MHz. These observations are made using a sniffer cable. As I said in my earlier email, I'd like to completely rule out a bad CAN-Do module before tearing into the receiver, especially this close to the symposium. I'm willing to try anything you suggest, but if you have another module available I'd like to try that first. 73, Juan - WA6HTP

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70 cm receiver inoperative with new CAN-Do module
by Juan Rivera 16 Sep '07

16 Sep '07

Stephen, Do you have another module that you could send to me? It's starting to look like I have problems with the original CAN-Do module and the receiver too. I can understand why the first module doesn't work since I removed and replaced the power supply components several times while attempting to troubleshoot the EMI problem. But the receiver is another matter. It's proven over months of banging around that it is a very robust unit. Neither PLL is currently working. So either I've got multiple failures on the receiver board or it's not being properly initialized. While I wait for your reply I'll be digging back into this and gathering test data. I'll send that out as soon as I gather it up... 73, Juan

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Module Temperatures & Eclipse
by Dick Jansson-rr 15 Sep '07

15 Sep '07

John, Juan, Bob D., & Bob M.: I have been preparing for my presentation to the Space Symposium on the subject of internal module heat sinks. As a concurrent subject, not in my paper, I have been preparing to discuss the temperatures that modules can achieve during a solar eclipse of the Eagle satellite. In this vein, things do get interesting and pretty darned chilly. I am showing the outboard, deployed solar panels getting down to the -117°C to -125°C! I also show body-mounted solar panels getting down to -81°C and other body sheet metal in the -60°C range. This analytic effort has pretty heavily exercised this new, high speed computer with some runs taking from 40 to 70 minutes, that is a lot of number crunching! The spaceframe temperatures for the start of the analysis was set at +10°C and modules at +20°C. For the modules I have analyzed both power off and with modest power dissipation in some modules. Some modules, with the necessary coatings to be able to handle 3.5W dissipation (e.eg. the URx in full operation), show a considerably deeper cooling than those with only the lowest emittance of a low-power module. Unpowered, or those with very low dissipation, show temperatures near to zero Celsius after three hours of eclipse while those of the higher emittance, for higher power operation, can get down to -30° to -38°C in that same time. This clearly illustrates why I have been pushing, wherever possible, to keep the module emittance low and to keep the module thermally decoupled from the spacecraft to the greatest extent possible. It also reinforces my high degree of upset with our German friends who painted not only the inside of their P3E modules black, but did me a favor by painting the outside black as well, failing to follow my instructions. The P3E situation will have to be dealt with as another issue. In eclipse, modules with low emittance and modest power dissipation show temperatures of +10° to +20°C. But the modules with the necessarily higher emittances, and dissipating a modest 1.0W of power, are only 10°C warmer than the unpowered condition, running at -25° to -28°C. I need to further refine this analytic model and to try different power dissipation situations. I felt, however, that it was necessary for me to report the results of these analyses to you at this time. These results are in line with the AO-10 telemetry for an eclipse condition, that was reported to me many years ago. 73, Dick Jansson, KD1K kd1k(a)amsat.org kd1k(a)arrl.net

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TS?
by Dick Jansson-rr 11 Sep '07

11 Sep '07

Is there to be a TeamSpeak meeting tonight? Is there anything to talk about? Dick Jansson, KD1K kd1k(a)amsat.org kd1k(a)arrl.net

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Going into the deep Echo archives.
by Tom Clark, K3IO 05 Sep '07

05 Sep '07

4 4

PAVE PAWS EMI
by Juan Rivera 05 Sep '07

05 Sep '07

Folks, In the San Francisco Bay Area it looks like most of the 440 MHZ FM repeaters will have to be shut down to avoid interference with the PAVE PAWS radar site at Beale Air Force Base in Marysville. That got me thinking that I might be able to detect the radar from my house even though it is almost 200 miles away and masked by terrain. Sure enough, I think I can. I've captured data and audio and posted it on my web and on EaglePedia. Click HERE <http://www.juanr.com/pages/hobbies/ham_radio/Eagle/PAVE_PAWS.htm> to read my log and listen to the audio. 73, Juan - WA6HTP

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AO-51 Multiband Antenna???
by Bill Ress 04 Sep '07

04 Sep '07

Perhaps one of you can detail the "multiband antenna" used with the SQRX receiver aboard AO-51. A perusal of Gould Smith's "ECHO" makes reference to it but provides no details. Does anyone have any in orbit data for this mode. What's the current status for its use? Regards and thanks...Bill - N6GHz

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Re: PAVE PAWS EMI
by Juan Rivera 03 Sep '07

03 Sep '07

Guys, I stuck a 30 dB amp on the Yagi, pointed it at Beale, and fed it into my HP 8566B spectrum analyzer. Here's what the 435 to 438 MHz satellite sub band looks like in max hold mode after about ten seconds... Juan

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Module Temperatures
by Dick Jansson-rr 01 Sep '07

01 Sep '07

Juan & John: I have finally been able to achieve some analytical results for projecting the temperatures of Eagle modules after two hour and three hour eclipse periods of no-solar heating. This has taken some time as I was struggling with the proper use of the SINDA software and had to call for some help which is why we pay money for the license, it comes with help when needed. (I should also note that with modern versions of this software and a pricey, but fast and capable, Dell computer, these analytic runs only required 18 seconds of real run time!) Nevertheless, I have been able to get some believable modeling results. The spacecraft model used is what I now call Small Eagle, the formerly proposed, but rejected 600x600x435mm spaceframe structure. While this is not as large as our currently planned hexagonal structure, the equipment bays are just about the same size as the larger spaceframe. I ran the model with one of the E05 20, 125x180mm, modules with coatings with an effective emittance of about 0.45, rather than 0.04, as would have to be done for the URx module. There was essentially no power dissipations in any module, at the most about 20mW in a few modules. This is granted to be an abnormal situation, but I wanted to see what happens. A later run was made with only a total spacecraft power dissipation of only 7mW were only lower by 0.1°C to 0.2°C lower temperatures. Modules started out at temperatures of +20°C and the spaceframe core structure at +10°C. The propellant tank was empty so it did not contribute any large thermal mass to delaying the cool-down. After two hours of eclipse the module temperatures were -5.2°C to -5.4°C (with the high emittance module being cooler), and after three hours of eclipse the module temperatures were -15.9°C to -16.2°C. The spaceframe core structure (equipment panels) were down to -10.2°C and -19.4°C respectively. For these cooling periods, the spacecraft outer skin temperatures ranged from -35°C down to -55°C. The deployed solar panels became a bit chilly, down to -113°C. A subsequent SINDA run was made with some kind of useful power dissipations in modules 0.5W to 1.0W not large but supposedly enough to keep things from getting out of hand, and with a total spacecraft dissipation of 16.5W. The two hour eclipse temperatures ran from -3.4°C (1.0W) to -3.9°C. In three hours of eclipse the module temperatures were at -13.3°C down to -14.0°C. In other words, these levels of power dissipation did not significantly warm the modules. The spaceframe core temperatures were at -8.0°C and -16.3°C respectively., just a few degrees warmer. What this data tells me is that specifying the cold temperature of a module does not have to be much lower than -20°C, and if it is operating at all they can be only a little higher. Cold module temperatures certainly do not need to be in the -60°C range. Beyond these statements, I shall not presume to be a specification writer. 73, Dick Jansson, KD1K kd1k(a)amsat.org kd1k(a)arrl.net

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Interesting article about fuel slosh in spin-stabilized satellites
by Alan Bloom 27 Aug '07

27 Aug '07

http://www.mathworks.com/company/newsletters/digest/2007/july/embry.html?s_…

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Publication
by Jim Sanford 24 Aug '07

24 Aug '07

Team: Sooner or later, we need to publish more. Publishing in QST would bring our efforts to widespread attention, which could help many things. Well, we may have our chance: * QST Wants You!: Have you ever thought of writing an article for QST? The official journal of ARRL, the national association for Amateur Radio, QST is always on the lookout for articles that explore all the possibilities of ham radio. We are looking for stories and articles that present a project or idea that is useful and engaging to most hams. The story you have had brewing in your head for months might be perfect for QST or the ARRLWeb. For the Web, we're looking for short (1500 words maximum), general-interest articles that tell a particularly interesting story. At least one photo to accompany the story is mandatory. Send your submissions to QST Managing Editor Joel Kleinman, N1BKE <qst(a)arrl.org>. If you've something to submit, go for it. I'll be happy to help as a reviewer or whatever, but I will not get in the way as a gatekeeper. If you want to write for QST, PLEASE DO!! 73, Jim wb4gcs(a)amsat.org

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Interesting article about VCXO phase noise reduction
by Jim Sanford 21 Aug '07

21 Aug '07

http://www.mwrf.com/Articles/Print.cfm?ArticleID=16332 Authors: Ulrich L. Rhode & Ajay Kumar Poddar, Synergy Microwave Corp. 73, Jim wb4gcs(a)amsat.org

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Update request
by Jim Sanford 21 Aug '07

21 Aug '07

Team: It is that time of year again. I need to compose my report of things accomplished, things projected to be accomplished next year, and projections of funds required to accomplish those things. Your unexpended funding requests from this year will NOT be rolled in to next yea -- we start over. I need your input (or negatives) on progress, projections, funds expended, and funds projected to be expended in 08. I need this information by 15 Sep 07 so that I can formulate my report to the BoD in Oct. Questions: Please contact me asap. Thanks & 73, Jim wb4gcs(a)amsat.org

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Info on U-band receiver changes
by John B. Stephensen 20 Aug '07

20 Aug '07

I've posted the schematic and assembly drawing for the U-band receiver test fixture on the U-band receiver page in EaglePedia just above the receiver fabrication section. This PCB was made to test a way to tune the matching networks for the narrow-band SAW filters. I also added a new second mixer and IF amplifier so that changes to reduce thermal dissipation in revision B of the receiver can be tested. Note that the average DC power consumed by first IF amplifier, second mixer and second IF amplifier drops from 870 mW to 370 mW. The circuit should exceed the specifications in the recently-revised U-band receiver requiremnts document. 73, John KD6OZH

2 1

Ron Bracewell, SK
by Tom Clark, K3IO 16 Aug '07

16 Aug '07

3 2

A power supply idea
by Tom Clark, K3IO 15 Aug '07

15 Aug '07

Since there has been a lot of discussion on the CAN-DO power supply considerations, I thought I would pass on what the Suitsat-2 people are doing. They seem to have settled on using the Newport NMV series of COTS isolated supply modules. I've attached 2 PDF files that describe the units for your information. 73, Tom

2 1

70 cm Receiver passband ripple - status
by Juan Rivera 14 Aug '07

14 Aug '07

All, Please click HERE <http://www.juanr.com/pages/hobbies/ham_radio/Eagle/passband_ripple.htm> to read the latest status on the 70 cm Receiver passband ripple. Bill, N6GHZ, has made good progress. 73, Juan

2 1

TeamSpeak conference
by Jim Sanford 14 Aug '07

14 Aug '07

Guys: Sorry I had to bail, but it was a REALLY URGENT phone call. You were all long gone before I got off the phone. Gould, pls send me a synopsis of the discussion after I left. Thanks & 73,. Jim wb4gcs(a)amsat.org

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Teamspeak conference tonight
by Jim Sanford 14 Aug '07

14 Aug '07

All: If there's any interest, I WILL be on at 2100 EDT. I see one other check in. Agenda would be Symposium and general status update. I've just been too busy to send out agenda before now, sorry. Way too many balls in the air right now. As always, anything else anyone wants to discuss... 73, Jim

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