February 2007 - Eagle (INACTIVE)

TeamSpeak conference for Tuesday 13 Feb
by Jim Sanford 23 Mar '07

23 Mar '07

Team: Our next TS conference will be Tuesday night at 2100 EST, 1800 PST, 0200 ZULU. The agenda is posted on the TeamSpeak conferences page of EaglePedia. Please add to it and join us Tuesday night. Note: I'll be travelling to VA and the weather is looking ugly (to be kind), so I might be a few minutes late. If I don't show up, please press on and take good notes. Thanks & 73, Jim wb4gcs(a)amsat.org

5 4

Info for the ANS Bulletins this week?
by JoAnne Maenpaa 22 Feb '07

22 Feb '07

Hi everyone, This seems to be a quiet week for general AMSAT and satellite info for the ANS Bulletins. Perhaps its an opportunity to provide a shot of longer range information about what AMSAT is up to? 1. Anything that can be said about Eagle? 2. Anything that can be said about the New Lab or University projects? 3. Anything that can be said about P3E? 4. Plans for Dayton? 5. Early info for the next Symposium? If you have anything please send the info to me by Saturday afternoon? I'll get it formatted into the final form for the bulletins ... just having the info helps the ANS editors a lot! Thanks! -- 73 de JoAnne K9JKM k9jkm(a)amsat.org Editor, AMSAT News Service

1 0

URx
by Dick Jansson-rr 20 Feb '07

20 Feb '07

John: Per your suggestion, I have examined your data for the U band Receiver. I shall first examine the power supplies for the receiver. The data that I have elicited from your information is as follows, powers in Watts: Device Dissipation Delivered U16 0.340 0.850 U17 0.411 U18 0.384 1.200 U19 0.108 0.090 U20 0.040 0.224 ------------ ------------ Totals 1.283W 2.364W For a grand total power dissipation of the power system of 3.647W. Of the delivered power you have identified two devices that suck up (U2 = 0.490W and U3 = 0.388W) a total of 0.878W. It is not clear where the remaining 1.486W is dissipated. Your help in identifying where this thermal energy is dumped in the module would be helpful, just to make sure that no stone remains unturned in this matter of handling these dissipations. Hot resistors could be an issue of concern...... You talk (somewhat glibly) of sinking regulator devices to PCB copper pads and such. For at least five devices, U2, U3, U16, U17, & U18 I consider that such mounting is not acceptable as such concentrated dissipations, exacerbated by the vacuum environment, must be treated more specifically in achieving heat sinking to the module housing. The module Base Plate, drawing E05 21, being of somewhat robust 1.6mm thick aluminum should help significantly in dissipating these module powers. More direct thermal coupling methods are going to be needed in this module to get that heat to the Base Plate. PCB thermal conductivities, even enhanced by added copper, are not good at all and cannot really be depended upon in these situations. With this module "pushing" the envelop of module power rating, baring a full heatsink module, it is clear that the coatings of the module will not be bare aluminum. This raises the ante in the picture of keeping command-level modules from getting too cold in the eclipse situation. The original concept for maintaining full control of the spacecraft through a 3 hour eclipse, where the spaceframe can be as low as -130°C or lower, low power, command-sensitive modules would not become dangerously cold, provided that their dissipations are indeed low and the thermal coatings highly reflective. If on the other hand we depend upon higher dissipation modules, such as this URx, then the module temperatures may be a concern in the eclipse situation. This is all subject to detailed analytic examination upon the construction of a full spacecraft analytic model, which we do not have at the moment, we first need a detailed mechanical design before having that analytic model. In any event, this URx presents a significant thermal challenge. Solving this challenge first needs an understanding of the physical bodies of these devices of the forenoted concern. Can you provide me with the physical information on these devices, either directly or by URL? Can you also respond to my earlier question on where the rest of the power dissipation resides? By one means or another we need to engineer a more direct thermal connection between these devices and the E05 21 Base Plate, which may require some inventiveness of our collective crania. '73, Dick Jansson, KD1K (ex: WD4FAB) kd1k(a)amsat.org ---------------------------

4 5

adding stuff to amsat.org
by Phil Karn 18 Feb '07

18 Feb '07

I had pizza with Brian Kantor WB6CYT Saturday night. He said somebody in AMSAT, possibly Rick, had asked for root access for the amsat.org machine so that various new functions could be added. I wasn't sure (and neither was Brian) of the specific new functions to be added, but they seemed to be various forms of engineering support. Brian is concerned, and I agree with him, that these additions might risk the stability and security of a stable machine already relied upon very heavily by everyone in AMSAT for email reflector and web services. Problems might come from the new services themselves, or from the much larger set of administrators with root access that would surely result. For example, counter to the assumptions of some, the amsat.org machine doesn't run Linux; it runs BSD Unix. They're similar in many ways, but there are crucial differences that anyone with root access must be aware of. Computers, even rackmount servers, just aren't so expensive or hard to come by that we have to cram everything on a single box. If there's need for another new server to handle AMSAT engineering-related services, I'm sure we could come up with a new box and host it at either UCSD (where Brian would manage it) or Qualcomm (where I would manage it.) Just let me know what's really needed, and we can make it happen. Phil

3 2

Proposed Eagle Antenna Arrays
by Louis McFadin 15 Feb '07

15 Feb '07

This is a repeat of the earlier e-mail. Here is a proposal for arranging the Eagle antennas that Stan Wood and I worked out today. By moving the 2M dipoles to the corners we have sufficient room for full sized elements over the ground plane. The 2M antennas should get about 8dB. Three L band patches in cavities should give us greater than 12 dB gain. By putting the S1,S2 and C band patches in hex shaped cups we maximize the available space. The cup arrays can be NC machined out of a solid blank and therefore attain precise control of the spacing. It may also serve as heat a radiating device. Each patch will be circular polarized and fed with a single feed from it's matching amplifier. The 70 CM Circular polarized patch should have around 6 dB gain. We will look at getting more gain on 70 cm. Seven S1 patches will be mounted on top the 70CM patch. They should get about 15dB gain. Tom's S2 interferometric patches are included. Omni antennas similar to that used on P3D will be required on the opposite side of the spacecraft. There should also be room for the Sun Sensors on both sides of the spacecraft. Lou McFadin W5DID w5did(a)mac.com _______________________________________________ Via the Eagle mailing list courtesy of AMSAT-NA Eagle(a)amsat.org http://amsat.org/mailman/listinfo/eagle Lou McFadin W5DID w5did(a)mac.com

3 2

TeamSpeak ports
by John B. Stephensen 14 Feb '07

14 Feb '07

What ports does TeamSpeak require other than 8767 for UDP and 9274 for TCP? 73, John KD6OZH

3 2

Regrets (buried in Boston)
by Robert McGwier 14 Feb '07

14 Feb '07

(Repeated from earlier since I did not see a return note) I regret very much not being with you tonight. I am in Boston trying to not get snowed in with Eric Blossom and others taking Cell processor training from Mercury. We left dinner long after the TS started because we left work long after the TS started! The Cell processor is a fascinating thing and has the potential to be a really disruptive technology but it is tedious to program. 73's Bob N4HY -- AMSAT Director and VP Engineering. Member: ARRL, AMSAT-DL, TAPR, Packrats, NJQRP, QRP ARCI, QCWA, FRC. ARRL SDR WG Chair "Taking fun as simply fun and earnestness in earnest shows how thoroughly thou none of the two discernest." - Piet Hine

1 0

Mail
by Dick Jansson-rr 14 Feb '07

14 Feb '07

Lately I have not been receiving Eagle email, owing to shifts in addresses that I was assured did not make for problems. For the moment, please add kd1k(a)amsat.org to your submissions to Eagle mail. Thanks. Dick Jansson, KD1K (ex: WD4FAB) kd1k(a)amsat.org ---------------------------

1 1

Re: 70 cm Receiver layout
by John B. Stephensen 13 Feb '07

13 Feb '07

I've added a paragraph to the U-band receiver page in EaglePedia that describes the PCB layout rules and the board materials. 73, John KD6OZH

1 0

Regrets
by Robert McGwier 13 Feb '07

13 Feb '07

I regret very much not being with you tonight. I am in Boston trying to not get snowed in with Eric Blossom and others taking Cell processor training from Mercury. We left dinner long after the TS started because we left work long after the TS started! The Cell processor is a fascinating thing and has the potential to be a really disruptive technology but it is tedious to program. 73's Bob N4HY -- AMSAT Director and VP Engineering. Member: ARRL, AMSAT-DL, TAPR, Packrats, NJQRP, QRP ARCI, QCWA, FRC. ARRL SDR WG Chair "Taking fun as simply fun and earnestness in earnest shows how thoroughly thou none of the two discernest." - Piet Hine

1 0

High Efficiency RF Amplifier Documents on Eaglepedia
by Tom Clark, K3IO 13 Feb '07

13 Feb '07

All: A few weeks ago I posted a couple of Univ of Colorado PhD theses in the files area on Eaglepedia that you might find of interest. The titles are "SWITCHED-MODE MICROWAVE CIRCUITS FOR HIGH-EFFICIENCY TRANSMITTERS" and "ROBUST DESIGN METHODOLOGY FOR CLASS-E AMPLIFIERS FOR MICROWAVE APPLICATIONS". I have a 3rd thesis that also looks of interest (entitled "BROAD BAND ANTENNA ARRAYS AND NOISE COUPLING FOR RADIO ASTRONOMY", but it's 54MB size causes Eaglepedia to barf on upload. Sometime, we need to figure a way to post BIG documents. Regards, Tom

1 0

Eagle Microwave Antenna Concepts
by Tom Clark, K3IO 13 Feb '07

13 Feb '07

1 0

doubling on TeamSpeex
by Phil Karn 13 Feb '07

13 Feb '07

Does anybody have any references on the internals of Team Speak? I'd like to figure out why doubling sounds so bad, and fix it if at all possible. It's pretty obvious from tracing the packets that everybody talks UDP to a central node (ts1.teamspeakhost.com) that repeats whatever it hears. There just aren't very many ways to do this. The central node can reflect the individual bit stream(s) exactly as received, without decoding. The listeners decode them. If more than one person talks at once, everybody sums up the PCM. (This is how Eagle's voice conferencing should work.) The other way has the central node decode the incoming packet stream(s), sum the decoded audio if there's more than one active stream, and re-encode the result into a single forward stream. This has the moderate advantage of not overrunning any slow dialup modems that might be in use. This isn't an FM repeater, so either way there needn't be any significant distortion when two people talk at once. Even with loud talkers and central summing, gain scaling would avoid clipping. The fact that the audio *is* so badly distorted whenever a double occurs, even when one talker isn't saying anything, means that something is broken somewhere. Perhaps the summing is being done incorrectly at the server. Maybe it's trying to sum mu-law PCM, which is nonlinear. The doubling distortion combined with the fairly long round trip delay makes this system a lot more fatiguing and a lot less usable than it could be. --Phil

1 0

Good tutorial on LO phase noise
by Phil Karn 13 Feb '07

13 Feb '07

http://www.am1.us/Papers/U10236%20Phase%20Noise-%20How%20Good-%20Gilmore.pdf Gilmore is a former Qualcommer. --Phil

1 0

Eaglepedia
by Dick Jansson-rr 13 Feb '07

13 Feb '07

Emily: How do I log into Eaglepedia as KD1K? My mail port is accepted, but Eaglepedia does not like the callsign..... Dick Jansson, KD1K (ex: WD4FAB) kd1k(a)amsat.org ---------------------------

1 0

Call Sign
by Dick Jansson-rr 11 Feb '07

11 Feb '07

Greetings: I was greeted this morning with the news of my new callsign, now KD1K, after a lengthy delay while the FCC got its software straightened out (nothing new about that!). Dick Jansson, KD1K (ex: WD4FAB) ---------------------------

2 1

P3D and P3E in Scientific American
by Bill Tynan 07 Feb '07

07 Feb '07

Thought you-all would be interested in this: The March 2007 issue of Scientific American contains an advertising section by the Czech Republic. On page CZ-10 of that section is a photo of P3D sitting on the launch vehicle. The accompanying text tells how Brno University of Technology is participating with "AMSAT". "Specifically, an on-board receiver with phase locked loop synthesizer has recently been developed for communication and commanding of the AMSAT Phase 3E Satellite which is to be launched in 2007. Formally a unique operations center was developed which helped with Phase 3D satellite control." 73, Bill, W3XO PS: BTW, I'm still not getting any Eagle mail, even though I have requested a change in address. I wish someone could do something.

1 0

[Fwd: Re: 3GHz]
by Jim Sanford 06 Feb '07

06 Feb '07

Team: This is the response I got to an email I sent after seeing the latest CQ-VHF. The successors to the HSMM effort are proposing a digital band plan, and have included us. They gave us 3400 to 3410, as an initial proposal. SO, digital guys, is this enough? In the discussions I've been part of, we spoke of 10 MHz as a minimum, and we spoke of it as nominal. How much do we REALLY need? What's been published is a proposal, the beginning of a conversation. I know we're a long way from saying, "this is what it will be," but can we articulate a needed bandwidth based on what we know now? I'd like to think that we can, but will defer to you who are smarter than me on these things. You who are more familiar with the international regulatory scene, is this a good freq range, or should we ask them to move? These guys like what we're doing and want to support us. Good things are happening! Thanks & 73, Jim wb4gcs(a)amsat.org -------- Original Message -------- Subject: Re: 3GHz Date: Sat, 3 Feb 2007 19:07:47 -0500 From: Paul Toth-NA4AR <ptoth1(a)tampabay.rr.com> Reply-To: Paul Toth-NA4AR <na4ar(a)ni4ce.org> To: Jim Sanford <wb4gcs(a)amsat.org> References: <45C51EDF.1060407(a)amsat.org> Jim... I passed it on to Drew Glasbrenner-KO4MA. Drew coordinates the Florida AMSAT Net on the NI4CE Repeater System (and other repeaters that link into NI4CE via Echolink). Drew indicated to me he would pass the bandplan up the line. I haven't seen what CQ published as yet. The bandplan reserves a window between 3.400 GHz-3.410 GHz for EAGLE and other satellite operations. /*If that is not suffficient, please let me know. The proposed bandplan is really more a suggestion for broadband network operations rather than something set in concrete.*/ ARBA, Inc. (Amateur Radio Broadband Alliance) came up with this to provide some guidance to those who want to build broadband wireless networks. We recognize that existing local activity on the band will need to be accommodated. I applaud the work you and AMSAT are doing. One of the missing links in Amateur Radio disaster communications has been digital satellite capability over an extended period (more than give or ten minutes at a time). EAGLE will help fill that need. Very 73 de Paul-NA4AR ----- Original Message ----- From: "Jim Sanford" <wb4gcs(a)amsat.org> To: <na4ar(a)ni4ce.org> Sent: Saturday, February 03, 2007 6:46 PM Subject: 3GHz > Paul: > I just read your article in CQ-VHF regarding HSMM work. In one of the > figures, you mention passing on a proposed band plan to AMSAT for > coordination with Eagle. > > Question: to whom did you pass that on? I'm the Eagle project manager > and have not seen it, other than the chart in the article. > > GOod article, congratulations. > > Thanks & 73, > Jim > wb4gcs(a)amsat.org >

5 5

Fw: Fw: 3.3 GHz ARBA Band Plan
by Andrew Glasbrenner 05 Feb '07

05 Feb '07

Here is a forward of the original message as I received it back from the eagle list, so I -know- it went to the list. There was some discussion afterwards which I have archived. 73, Drew KO4MA ----- Original Message ----- From: Andrew Glasbrenner To: eagle list Cc: Dave Anderson ; Paul Toth-NA4AR Sent: Saturday, November 04, 2006 6:21 PM Subject: [eagle] Fw: 3.3 GHz ARBA Band Plan Hi Guys, I am forwarding this email to the Eagle amsat list, which consists of just about everyone involved with our new satellite effort. Hopefully the right person will respond so we can work together on this issue. 73, Drew KO4MA Amsat-NA VP Operations LM 2332 ----- Original Message ----- From: Paul Toth-NA4AR To: ko4ma(a)amsat.org Cc: Dave Anderson Sent: Saturday, November 04, 2006 5:53 PM Subject: 3.3 GHz ARBA Band Plan Drew... A new group call ARBA, the Amateur Radio Broadband Alliance, has formed in the ashes of ARRL's HSMM Working Group. Both Dave Anderson and I are part of ARBA. One of the things we are working on is the development of a band plan for the 3.3 GHz to 3.5 GHz allocation. I know that AMSAT is planning something for Eagle that makes use of the 3.3GHz band. Would you please review the chart below and provide some input to allow this band plan to peacefully co-exut with whatever AMSAT is planning? Please feel free to share with others in the AMSAT leadership. 73 de Paul-NA4AR ARBA BAND PLAN 3.3 GHZ - 3.5 GHz 3300-3310 3310-3330 3330-3340 3340-3350 3350-3370 3370-3380 3380-3390 3390-3410 3410-3420 3420-3430 3430-3450 3450-3460 3460-3470 3470-3490 3490-3500 -------------------------------------------------------------------------------- _______________________________________________ Via the Eagle mailing list courtesy of AMSAT-NA Eagle(a)amsat.org http://amsat.org/mailman/listinfo/eagle

1 0