- Eagle (INACTIVE) - mailman.amsat.org

Florida AMSAT Net Will Host W2GPS This Thursday
by JoAnne Maenpaa 13 Jan '08

13 Jan '08

AMSAT President, Rick Hambly, W2GPS will join the Florida AMSAT Net, Thursday Jan 17, 2008 from 7:30 - 8:30 pm EST to give a short status report and field questions. This net links repeaters all over Florida and via EchoLink so there is ample opportunity for those that want to listen or ask questions. The EchoLink nodes to connect through are: KG4YZY-R or N4HHA-R. The net's purpose is to provide a platform for hams with amateur satellite interest to meet and discuss topics of interest. All amateurs are invited to check in. Expect other AMSAT Officers and Board members to participate over the next few months. -- 73 de JoAnne K9JKM k9jkm(a)amsat.org

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AMSAT Web Page Updated
by JoAnne Maenpaa 12 Jan '08

12 Jan '08

Hello everyone, The http://www.amsat.org web page has been updated with an executive summary of the EAGLE engineering team meeting we held on Tuesday, January 8. Goal is to provide general information via the web and mail lists to the amateur radio community. We plan to publish complete details in the Journal so paid members receive this as a benefit of signing up. -- 73 de JoAnne K9JKM k9jkm(a)amsat.org

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Mumble
by Bob McGwier 10 Jan '08

10 Jan '08

FYI, there is absolutely NO comparison between Mumble and Team Speak. Mumble is awesome and Team Speak SUCKS. It allows you to adjust for the lowest latency your computer can tolerate. It is so good you can carry on two way casual conversations as if you were on the telephone. There is latency, but it is in no way as bad as TeamSpeak. If we do the Ham Radio server change over with Eric Ellison, Eric will need to set it up as multiple servers on separate ports, one for each room. But it is very very light weight. The speex speech quality is just fantastic. I am going to run some Flex Radio developer tests, where we get all of the developers on to see how it scales. I would not want to have all of AMSAT Engineering change over and it fail when we have the kind of great turn out we had last week. Bob

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Teamspeak isn't working for me
by Matt Ettus 08 Jan '08

08 Jan '08

If somebody could help me figure out why I am muted in teamspeak and can't send or receive, that would be helpful. There is no unmute option in the menus, but clicking Self/Mute Microphone and Self/Mute Speakers don't unmute me. Otherwise, you're not getting an ACP report... Matt

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Team Speak
by Robert McGwier 08 Jan '08

08 Jan '08

Tonight at 9 P.M. Eastern time engineering will meet on the Amateur Radio Developer's Team Speak server. I didn't realize why Matt hated it so much until I realized the default password for access to the main system is Flex4U. ;-). It was originally started up by owners and users of the SDR-1000 by Flex Radio but it is now the default meeting place for Here are your instructions copied from the password protected EaglePedia page. I am happy to announce that Dave Hartzell has volunteered to take on the reorganization of the EaglePedia content. I am very hopeful that with his leadership and contributions from the individuals involved, it can meet the clear promise it holds. I am sitting in the AMSAT Engineering room with away selected. 73's Bob N4HY Getting Started 1. Download and install the TeamSpeak client. 2. Bring up TeamSpeak client. 3. Click Connection 4. Click Connect 5. Right Click Servers 6. Click Add Server 7. In the Label field, enter AMSAT (could be anything you want.) 8. In the Server Address field, enter "70.84.228.202:9274". Include the colon and port number, but do not include the qoute marks ("). 9. In the Nickname field, put whatever you want. Suggest at a minimum, name and callsign 10. Select Anonymous 11. In the Server Password field, put "Flex4U" as password without the quotes. 12. In default channel, enter "AMSAT Engineering" without the quotes. 13. In channel password, enter "Eagle" as password, again without the quotes. [edit] Connecting to TeamSpeak 1. Click connect. 2. In Settings, select Sound input/output settings. 3. Leave everything at the default, except select Push to talk mode. You'll then be asked to select a key for your PTT switch. I use the right <CTRL> key (the left one on my laptop); some use the spacebar. Whatever you like, but you probably want a key which does NOT go into the keyboard buffer. Note that this is like a PTT switch on a radio, you must _hold it down_ to transmit. 4. Leave everything else at default; select CLOSE. [edit] Once You Connect This should work; I'll be listening. Amazing how WELL it works on my dialup! If by chance, I'm not hearing you but you're hearing me: 1. Open your sound card mixer application (varies with windows version and sound card.) Make sure the microphone is enabled on the INPUT (may be called RECORDING) side. Probably should be disabled on the Playback side. If you have any questions about TeamSpeak please post them to the Eagle Mailing list.

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Proposed agenda for Jan. 8 TS meeting
by Robert McGwier 08 Jan '08

08 Jan '08

This is a proposed agenda for next week's meeting. Poor Howard! If he cannot make it for that meeting, we will get the report from him earlier and deliver it. Please send me your modifications. I will contact each of the proposed presenters directly. http://n4hy.org/AMSAT_Engineering_Meeting_2008_i.pdf Barry Baines is the leader of the meeting and the time enforcer. 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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SBD Varactor Help
by Tom Clark, K3IO 07 Jan '08

07 Jan '08

Many of you have seen my idea of a voltage tunable phase shifter for Eagle's S2 & C-band arrays. If you haven't, a copy of my paper from the 2007 AMSAT Space Symposium is available for download at http://mysite.verizon.net/w3iwi/electronic_scanning_antennas.pdf. I haven't had time to do much on the project the past few months, but in the initial breadboard I found that conventional varactor diodes simply create to be a discontinuity at the tap. I've done a little testing with a resistor in series with the varactors, but I have no progress to report. Matt Ettus and others have been providing me with a lot of reprints on NLTL (non-linear transmission lines) used to generate picosecond risetime pulses, and it is very interesting. The web has a lot of relevant publications, including the voltage-steerable array described at http://tempest.das.ucdavis.edu/mmwave/NLTL/NLTL.html. At least these publications show me that my idea is not totally screwy. After researching the topic, I have come to realize that what we need are not varactors used for tuning VHF radios, but rather some diodes with MUCH smaller junction capacity. This seems to dictate the use of Schottky Barrier Diodes (SBD) as varactors. Microwave SBDs are used as parametric frequency multipliers and mixers up into sub-mm wavelengths. In doing literature searches, I came across the MACOM 44700 series of diodes (PDF attached) that look pretty good. I wonder if we have some talent here in the EAGLE group who have experience with low-capacity (range 0.1-2 pf or so) varactors who can point the way to some suitable parts we might try. 73 & Happy New Year -- Tom

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[Fwd: Maxwell 3D Training, Burlington MA, January 17-18]
by Tom Clark, K3IO 05 Jan '08

05 Jan '08

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Hello - D. Goncalves
by David Goncalves 04 Jan '08

04 Jan '08

Hello All, I think I was invited here by Robert McGwier. I would like to say hello to all of you, and Happy New Year. I am David Goncalves (W1EUJ), I live in Lexington, MA, have had some experience in working on a satellite project (RAFT), and work by day as an electrical engineer designing hardware for heart support/replacement devices. I work currently with FPGAs (using VHDL) for backup control of pneumatically driven blood pumps. I think my skills might be of use here. In particular, I offered to help with the PWM control, and possibly other tasks. I did get an education in LTI systems, DSP and digital design from Northeastern University, from which I graduated in 2004, so the topics here are not new to me. I understand that the Xilinx Spartan (I hope I have that right) is being used here, and I can start by getting familair with that hardware. Robert, as I came on to help you, I await your 'command'. To anybody and everybody else, if there is documentation that I should go read, point the way, and also good luck in your endeavors. -- David Goncalves

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Re: [Bod] Re: Proposed agenda for Jan. 8 TS meeting
by Robert McGwier 02 Jan '08

02 Jan '08

We will investigate having Eric set up a server. There is no mac distributable but there is source and details on how to make it. For the time being, we are sticking with what works. We have to conduct business and not fight a new system. When we know it works, is stable, doesn't cause us to lose anyone because it doesn't work on their computer (which is what TS did for us), we will give it a test drive. For me, this is off topic as of now. Bob Lou McFadin wrote: > TS seems to work fairly well. I wouldn't wan to switch to anything that > didn't include a Mac OSX version. > > Louis McFadin > 701 Deerwood Ave. Orlando Fl 32825 > 407 658 8179 > w5did(a)amsat.org > -- 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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Re: [Bod] Re: Proposed agenda for Jan. 8 TS meeting
by Matt Ettus 02 Jan '08

02 Jan '08

Lou McFadin wrote: > TS seems to work fairly well. I wouldn't wan to switch to anything > that didn't include a Mac OSX version. There is a mac version of mumble. http://mumble.sourceforge.net/BuildingMacOsX Matt

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Engineering Management addition
by Robert McGwier 31 Dec '07

31 Dec '07

I have asked Barry Baines to take on a substantial role in engineering project management. He is a perfect fit for the job. He and I will be putting together the agenda for next Tuesday. I have one more in a holding pattern. ;-) Hopefully we are all together by next Jan. 8. Expect a preliminary agenda by THIS Tuesday. I will expect to have all of your requested revisions to the topics to be covered by the weekend so we can have people who will be asked to prepare things for it. I am still asking a few questions about timing. I have gotten a very good response to my call for help. Some new folks showed up and some who have been waiting for action have jumped back in. I am confident we can make a good start to 2008 and BUILD SOMETHING. Happy New Year, 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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Please welcome
by Robert McGwier 22 Dec '07

22 Dec '07

Please welcome new "recruits" Phil Lanese, Jeff Mock, and Jacob Spencer. Jacob and Jeff have lots of FPGA experience and Phil Lanese, besides being a packrat is interested in helping with RF design and prototype and testing. Again we are going to have a TeamSpeak meeting on January 8. I will send out a proposed agenda and requests for input, as well as instructions for how to get onto TeamSpeak and the server. I am actively working on project management activities now and hope to report more by January 8. 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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Early 2008
by Robert McGwier 21 Dec '07

21 Dec '07

Greetings! We have several projects right now in engineering and I am looking for some volunteers to take on some individual pieces of this after Jan. 1. Please help me recruit talent that can work on these projects for a short intensive period. The goal will be to demonstrate as much as possible at Dayton and even more by October. This means that beginning in January we have to move out smartly. I hope this group will step up and take on either individual pieces or help recruit volunteers to do some of this work. We are taking on two projects with the Suitsat2 hardware should it ever become available. Suitsat 2 itself, and an on the air demo, to begin with in Florida through the coordination efforts of Drew. The Florida demo is easier than Suitsat2 but still requires work. We have hardware from DEMI (nice, already in Florida!) that will allow us to put an SDX on a tower there at about the 900 foot level which will cover a huge piece of Florida. The other project is the HASP balloon project. This uses the Suitsat 2 hardware, again, assuming availability. We need to have an SBC to talk to and reload this thing as we update and upgrade code for the Florida experiment. I have not vetted the Suitsat 2 IHU for this purpose because I have never seen it, can't size it, or even tell you if it runs. This will be remedied in January. In addition, we need to get ready for the pursuit of a working prototype of the full SDX. I talked to Marc Franco a couple of weeks ago. He and his wife have a beautiful new baby and Marc is working again on the amplifier. Marc Franco has made steady progress on the driver and amplifier. He is working through an oscillation problem in the driver in an attempt to NOT have to solve it by gain reduction (lowering the overall efficiency). John Stephenson appears to have solved the critical matching problem for the SAW filter in the 70 cm RX. The goal for this would be to get it ready for on the air testing in time for Dayton and then deploy to the Florida site to take over from the Suitsat hardware. Here we could arrange some torture tests for the Stella. I have most of the hardware details on Howard Long's version of the SDX. I still need a late version schematic and the latest code but he has shared with me many of his parts selections, reasons, etc. Karl has marked up the P3E transponder in a way that tells Howard how to add SDX to the mix, right down to voltages, current, impedances, etc. I will arrange to get the latest code from Howard. I have two Lyrtech boards which are XC2V3000 Virtex 2's and TMS320C6713 DSP. These boards are to be used to prototype code for the HELAPS modulator and a small channel version of the ACP. We need some FPGA work done on the Virtex 2 for SDX and for ACP. The Virtex 2 is overkill for the SDX. We need it to do rectangular to polar conversion, a PWM for the modulus or envelope channel, and a few other minor tasks. The Virtex 2 is a capable part but it will not support the full ACP. Nevertheless, it will certainly allow us to develop the basic ACP FDM up and TDM down demod, remod cores we need. The difficulty in dealing with this card is that it really does have to have expensive tools. I have them and while Rick has a copy of the Lyrtech, but I am not sure this is optimal if we can find a volunteer with FPGA experience and the time to work. Rick has both real work and institutional difficulties in AMSAT to deal with. Ideally, I would find a different candidate to help with this. This means that I am looking for someone with a) access to Matlab and b) FPGA experience and c) access to TMS320C6713/6726 development tools. This is a tall order but it is the fastest way to a working prototype to "show we can". There is absolutely no reason we cannot begin the prototype development of an upconverter and a downconverter for the ACP. I can test the ACP at IF with the other Lyrtech board being used for ground terminal development. We need to do work on the modulator, demodulator, FEC, decoder, etc. for this. But we need to come up with some preliminary thinking on devices to be used at 3.4 GHz and 5.7 GHz for the generation and reception of hard limited constant envelope signals and some prototyping needs to be done. I would like to call for a meeting as early as possible. I don't care if we have multiple meetings but we need to organize our activities around getting some specific tasks and deliverables into our thinking by not later than mid February. We need to set realistic goals for what can be accomplished by a) Dayton and b) the annual meeting. I will be on TeamSpeak on January 8 for a meeting of anyone who wants to show up and talk about these activities. I hope to report on some definite progress on many things facing us, including a detailed ITAR situation report from Rick. That is moving along but we are at the very hard spot of agreeing on language for the technical assistance agreements. We need to aim for a serious meeting as early as possible in and probably early February. Please think about your availability. This note is an informal heads up to expect a larger and more detailed mailing to come out while I have 5 days at home. Happy holidays, 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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[Fwd: Maxwell 3D Training, Burlington MA, January 17-18]
by Tom Clark, K3IO 20 Dec '07

20 Dec '07

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Module Drawings
by Dick Jansson-rr 19 Dec '07

19 Dec '07

I have posted to Eaglepedia the complete sets of drawings for the new E05 60 Module and E05 65 HS Module. This later one uses HS to mean Heat Sink, where the module is equipped with a sizable heat sink to handle power devices as would be used in Eagle Mission transmitters, or other module functions with power dissipations greater than ~5W. These drawings are posted for your use and review. '73, Dick Jansson, KD1K <mailto:kd1k@amsat.org> kd1k(a)amsat.org <mailto:kd1k@arrl.net> kd1k(a)arrl.net

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updated U receiver info
by John B. Stephensen 17 Dec '07

17 Dec '07

An adjustable matching network removes the ripple in the U receiver passband. I've added information at the end of the U-band receiver page in Eaglepedia. 73, John KD6OZH

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Time Hackers
by Tom Clark, K3IO 12 Dec '07

12 Dec '07

Many of you know that I (along with others like W2GPS, N4HY, K8RQ, N8UR etc) have long-standing interest in high-accuracy timekeeping (especially involving GPS). You might find this WIRED article interesting (http://www.wired.com/science/discoveries/news/2007/12/time_hackers). Several of you know about Tom Van Baak (no call) and his time/clock exploits; Tom has been a friend ever since he became interested in atomic clocks. The article doesn't mention it, but Tom (who signs his messages TvB) has TWO hydrogen maser clocks in his lab. Photos of the clock labs at TvB and N8UR home QTHs, see the gallery at http://www.wired.com/science/discoveries/multimedia/2007/12/gallery_time_ha…. In the article you will also find mention of John Ackerman (N8UR) in Dayton. John has served as TAPR's president and has recently helped TAPR/AMSAT in developing a GNU-like Open Source Hardware license. For those of you interested in the topic, N8UR runs the "Time Nuts" Email listserv. Details can be found at https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts. 73 & Seasons Greetings -- Tom

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THE TALKING DOG
by Dick Jansson-rr 28 Nov '07

28 Nov '07

I'm wondering if we can recruit this dog to help us in the satellite design world. J Dick Jansson, KD1K <mailto:kd1k@amsat.org> kd1k(a)amsat.org <mailto:kd1k@arrl.net> kd1k(a)arrl.net -----Original Message----- While driving around the back woods of East Texas, on one back roads I saw a sign in front of a broken down shanty-style house: "Talking Dog for Sale." Well I needed a break so I stopped to see what the deal was. I went into the backyard and see a nice looking Labrador retriever sitting there. "You talk?" I ask. "Yep," the Lab replies. Well after I got over the shock of hearing a dog talk, I asked "So, what's your story?" " Ah shucks there ain't much to tell. Is that a VUU screwdriver antenna on your truck out there?" "How did you know that," I ask? The Lab looks up and says, "Well, I'm a ham radio operator. I got my Ticket when I was a young pup and in no time at all I had my 5 band DXCC in Phone and CW. The CIA heard about me and asked me to do some spy work for them. I would hang around the communications centers and with my keen hearing I could copy the transmissions. Because no one figured a dog would be eavesdropping, I was one of their most valuable spies for eight years." Copying high speed CW all day really tired me out and I knew I wasn't getting any younger. So, I decided to settle down. I retired from the CIA (8 dog years is 56 CIA years) and joined a ham radio club. In fact I won first place in the Oklahoma OSO Party two years in a row. Then I had a mess of puppies and got away from Ham Radio for a while. I sure miss my radio. Why don't you buy me and I'll be your CW operator in the Texas QSO Party. I said "let me see what I can do." I went back in and asked the owner what he wants for the dog. "Ten dollars," the guy says. "Ten dollars? This dog is amazing! Why on earth are you selling him so cheap?" "Because he's a liar. He never did any of that stuff. He's just a No Code Technician."

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AMSAT's Power Developments in the news
by Tom Clark, K3IO 22 Nov '07

22 Nov '07

Many of you have heard that Lew McFadin (W5DID), working with Steve Bible (N7HPR) and Steve's colleagues (especially Keith Curtis) at Microchip (the PIC people) have been working on a next generation power conditioning system. The basic idea is to have a power charge/discharge conditioner for each cell of the spacecraft's battery pack. This will allow the use of several different battery technologies (NiCd, NiMH, LiIon, etc) and also some of the new "super capacitors". Some of you who were at Dayton may have seen the breadboard mockup of system that Steve brought and Lew was showing. Lew was also showing some ~2000 Farad(!) 3 volt capacitors (some of us dubbed them "flux gate capacitors"). The SuperCap developments have been exploding of late. One immediate service is for regenerative braking in hybrid and electric vehicles, since the capacitors seem to be able to withstand a (virtually) infinite number of charge/discharge cycles, and then can "soak up" & discharge huge currents -- must faster than any chemical batteries can do. Batteries store watt-hours of energy, while capacitors handle large numbers of watts of power. One German light-rail system employs a total of 600 2600Farad capacitors for regenerative braking. Some US electric buses have capacitor banks with 144 18Farad capacitors that deliver 400 Amps at 360 Volts. Today I received the 11.15.07 edition of Electronic Design magazine, and there is an interesting technology review paper entitled "Get the Lowdown on UltraCapacitors" starting on page 45; the article is available online at http://electronicdesign.com/Articles/ArticleID/17465/17465.html. Starting on page 50 (the 3rd page of the online version) The AMSAT/MicroChip effort is described along with schematics (figure 6, also http://electronicdesign.com/files/29/17465/Figure_06.jpg). The closing paragraph (which doesn't mention the planed use of these concepts on Suitsat2) says: > Microchip worked with AMSAT-NA, the not-for-profit private organization that develops > amateur-radio satellites. AMSAT’s next big project, the Eagle satellite, is slated for > launch in March 2009. To make Eagle function for decades, it will have a power system > based on this work that combines solar panels, lithium-ion batteries, and ultracaps > in an integrated power system that will optimize the use of each of those components. Pretty good publicity! 73, Tom

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Thanksgiving Week
by Robert McGwier 20 Nov '07

20 Nov '07

I hope this note finds everyone on the Eagle and Suitsat teams having a pleasant mid-November. For those in the United States, I hope you have a pleasant Thanksgiving hiatus. For the first time in months, I will have four days in a row at home! Tomorrow I go to the intial meeting at the Laboratory for Telecommunications Sciences at U. Md. for the stand up of my team and the kick off of my project. This has been the most brutal six months of my career in the dealing with bureaucrats and it has played hell with most aspects of my life. I have not stayed with Tom and Elizabeth in weeks. I have foresworn Gin and Tonic for weeks so you know it must be bad! After tomorrow's kick off and following the Thanksgiving break and the GnuRadio Hackfest (next week and now a major activity at my work place) I expect to return to "full time HAM work" with a very large agenda. This past Friday night I spent time talking with Bob Davis and Saturday, I had a very good half a day with him at the Lab. He is just doing a great job but we have been allowing him to carry the load for us while trying to do a full time job of his own. I am hoping that more people will start to go over. AMSAT will support this activity. We are starting some fun things at the Pocomoke facility and with U. Md. E.S. The HASP balloon project has been joined by AMSAT through Hawk/AMSAT in Pocomoke. It will give us an early opportunity to fly our Suitsat 2 payloads and we will be pushing to finish those pieces (all of them) in time to get on the balloon. This will give us the focus we need to finish the RF pieces and the experiment interfaces. We are going to build the frame of Eagle in the lab this year. We hope to stand up an AMSAT Institute, a two week "camp for teachers" at UMES and Hawk in the coming summer. Bob and his volunteers have done a great job getting a lot done in the last few weeks. http://n4hy.smugmug.com/gallery/3841264 Soon the fire systems will be in and a certificate of occupancy granted and work can begin! Hawk has a Cubesat project. It is to be launched from Wallops on the DelMarVa peninsula next summer unless there are slips. Our labs are in the Hawk Institute for Space Sciences offices as seen in the photo's in the gallery above. There is work that needs to be done to help finish this off. I do not have a list of tasks yet but that will be coming soon. I will be doing my best to set a good example by going down there on two Friday's a month and working through most of Saturday starting in December "on my way home" from Maryland to NJ. This will be reasonably straightforward to figure out. N2HPE is off every other weekend and I will work in Md when she is working. We can accomplish a lot in the coming months and I hope you will soon feel the enthusiasm I do for the prospects for the end of the year and also 2008. Have a great week and Happy Thanksgiving to my U.S. friends. 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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[Fwd: Power & Signal Integrity with SIwave - Dec. 12, 8:30 a.m.-5:00 p.m. EST]
by Tom Clark 20 Nov '07

20 Nov '07

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[Fwd: HFSS Advanced Antenna Design Class - Dec. 11]
by Tom Clark, K3IO 16 Nov '07

16 Nov '07

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FYI -- ANSOFT HFSS
by Tom Clark, K3IO 13 Nov '07

13 Nov '07

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Re: [amsat-bb] Re: FYI -- One Laptop per Child (OLPC) Opportunity
by Tom Clark, K3IO 11 Nov '07

11 Nov '07

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