September 2006 - AMSAT-BB - mailman.amsat.org

Re: 10mtr and Galileo
by Miroslav Kasal 11 Sep '06

11 Sep '06

Hi OMs, Yes, the Galileo spectrum null for both E6 orthogonal signals goes out on 1263.4 MHz. For that reason the P3E L-band receiver local oscillator is synthesized and receiver is possible to retune from 1268.800 to 1263.300 MHz (center of the analog passband) by command from the Earth. On 1268.52 MHz we expected one of the power spectral density peaks of Galileo sigs. I already offered participation on Eagle project in the field of L-band receiver. Mirek OK2AQK P3E L-band Rx designer >> Hi John, >> >> Consider this....... >> >> >> 4) I understand that the P3E folks have already worked out a solution by locating their L-Band operations in what will be a Galileo spectrum null. If that is the case, then the P3E folks are really using some good "science" to develop their satellite L-Band operations. Good for them!! Hey - I'm not in the thick of it - but it seems there are some serious gaps in communication between AMSAT-DL and AMSAT-NA even though we read about glimpses of real technical exchange. I hope we're not falling for the NIH (Not-Invented-Here) syndrome. >> >> Regards...Bill - N6GHz >> >> >> -----Original Message----- >> From: amsat-bb-bounces(a)amsat.org [mailto:amsat-bb-bounces@amsat.org]On >> Behalf Of John B. Stephensen >> Sent: Sunday, September 10, 2006 7:47 PM >> To: jules(a)g0nzo.co.uk; amsat-bb(a)amsat.org >> Subject: [amsat-bb] Re: 10mtr and Galileo >> >> >> What bothered people is the fact that we need high power L-band uplinks and the statement in the report that "there is the potential for most amateur 23 cm transmissions to interfere with Galileo unless the Galileo receivers are designed and built to withstand it". >> >> 73, >> >> John >> KD6OZH >>

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S-band continued.
by john hackett 11 Sep '06

11 Sep '06

Aw C'mon guys, You don't really expect the b.o.d. to pay any attention to the opinions of those whom actually "operate" on amateur satellites - not to speak of the paying public with their "donations". Be smart, tell 'em what you *don't* want - then maybe you'll get what you *do* want. (tongue in cheek). Remember ... they know better than than you! what you want - as I've oft times been told - (by b.o.d. members) (... and yes, I'm fully aware of the following "sound" reasons for some of the decisions). 1) We have to adhere to the "constructors and planners" wishes otherwise the org: will die. 2) This is Amsat-NA, we can't oblige 3rd world country wishes - (even if we DO accept their donations). 3) Cutting edge technology - (read: fewer and fewer participants/the affluent only). 4) Launch criteria has changed - (money, money, money). I just wonder if the simple mode-A that actually worked v high tech that doesn't - (for whatever reason) - has sunk in yet ... apparently not. In my opinion, RS-10 and FO-20 were the most popular and widely used amateur radio satellites (worldwide) - neither of which, incidentally, had anything to do with Amsat. ... and before you turn on the flame throwers, yes, I AM doing my bit for the amateur radio satellite fraternity ... and I AM entitled to an opinion - (though I am NOT asking you to agree with it) - it does appear however that there is a continuing conflict of interests between the "planners" and the "users". 73 John. <la2qaa(a)amsat.org>

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AO-51 Mode L/S
by Francesco Grappi 11 Sep '06

11 Sep '06

Hello All, This morning at 07.12 UTC, I had nice qso with OE6AG on Ao-51 L/S mode Strong signal into 90 cm. dish with patch feed and keps downconverter only a little bit qsb, but signal was very good. Excellent mode L/S thank you Willy for qso Thank you the AO-51 Commander Team 73" Francesco IW4DVZ

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Re: 10mtr and Galileo
by Bruce Rahn 11 Sep '06

11 Sep '06

John B. Stephensen wrote: > The issue isn't technical, but regulatory. What will governments do > worldwide in the next 20 years? We can't change frequencies once we get > within 2 years of the first launch and must live with the choice for the > life of both Eagle satellites. Should AMSAT spend their members money on two > satellites that may become inacessible in the future or pick the safest > frequencies? > > 73, > > John > KD6OZH John, I.E., it is based on a perceived political climate. That's what I thought, thank you and there is still no sound technical reason why the politicians should prevail...sigh..but we know they follow no logic. Bruce -- Bruce Rahn Wisdom has two parts: 1. having a lot to say; and 2. not saying it!

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Re: Eagle Satellite Design
by George Henry 11 Sep '06

11 Sep '06

A number of BB participants have already indicated that they WON'T fund a satellite that they don't want, which begs the question: will Eagle fly, period? Has the design committee effectively killed the bird by killing enough interest? I hope not, but time will be the judge. I am disappointed by the loss of mode S, but would rather at least have a V/U HEO than no HEO. (I still maintain that the dire predictions for 2.4 GHz will not come to pass) ----- Original Message ----- From: "Emily Clarke" <emily(a)clarke-design.com> To: "George Henry" <ka3hsw(a)earthlink.net> Sent: Saturday, September 09, 2006 2:33 PM Subject: Re: [amsat-bb] Re: Eagle Satellite Design > > Most likely AMSAT wouldn't let you do it - it would interfere with the > primary mission. Besides - why should AMSAT members fund a satellite they > don't want, and they have to pay even more to rent space for a payload > they do want? > > 73, > > Emily > > > At 11:09 AM 9/9/2006, you wrote: >>So, how much to rent one of the TSFR spaces? Maybe all of us who still >>believe in S-Band could pool our funds to fly our own transponder..... >>fund >>the mode instead of the bird? >> >> >>----- Original Message ----- >>From: "Rick Hambly (W2GPS)" <w2gps(a)cnssys.com> >>To: <amsat-bb(a)amsat.org> >>Sent: Saturday, September 09, 2006 5:21 AM >>Subject: [amsat-bb] Eagle Satellite Design >> >> >><snip> >> > >> > c) There are at least two TSFR (This-Space-For-Rent) packages that >> > could >> > possibly contain other RF or other payloads, conditioned on the >> > availability >> > of power, antenna space and compatibility with the primary payloads.

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Re: 10mtr and Galileo
by Bruce Rahn 11 Sep '06

11 Sep '06

John B. Stephensen wrote: > Galileo transmits on 1260-1300 MHz and 1215-1300 MHz is now allocated to > global positioning systems (up to 5 of them). Amateur transmissions can > desense the earth-based receivers. Tests on U.S. GPS receivers showed > that a > 1W EIRP CW signal 10 km away would cause inteference. It would be > better if > 1260-1270 MHz was a downlink for amateur satellites. > > 73, > > John > KD6OZH John, You are neglecting real word conditions...future civilian airborne GPS/GNSS/Galileo receiver systems are going to have to incorporate anti-jam capabilities. A few do already and changes in the signal coding for the new civilian GPS downlink will have a much more robust capability when it comes to interference rejection. I also believe Galileo will too employ a more jam resistant signal waveform. There are much greater threats to these systems than ham operators from a real-world technical perspective. However, I will concede that government agencies may eliminate amateur use of L-Band for political reasons...an easy, but meaningless way for them to show they are taking action. However, until and if the hammer comes down, there are currently no strong technical reasons to eliminate L-Band uplinks. Bruce -- Bruce Rahn Wisdom has two parts: 1. having a lot to say; and 2. not saying it!

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Re: 10mtr and Galileo
by joseph Murray 11 Sep '06

11 Sep '06

John I am confused Please provide something to cure my problem I believe at this point that the Galileo bird transmits to receivers on the ground in the current amateur mode L up link spectrum. Right or wrong? What frequency in the same amateur L mode spectrum is the Galileo using for receiving. Joe Murray K0VTY Amsat #860 ============== On Mon, 11 Sep 2006 02:47:22 -0000 "John B. Stephensen" <kd6ozh(a)comcast.net> writes: > What bothered people is the fact that we need high power L-band > uplinks and > the statement in the report that "there is the potential for most > amateur 23 > cm transmissions to interfere with Galileo unless the Galileo > receivers are > designed and built to withstand it". > > 73, > > John > KD6OZH > > ----- Original Message ----- > From: <jules(a)g0nzo.co.uk> > To: <amsat-bb(a)amsat.org> > Sent: Sunday, September 10, 2006 23:37 UTC > Subject: [amsat-bb] Re: 10mtr and Galileo > > > > Just for the record, the first Galileo satellite has already been > launched: > > http://news.bbc.co.uk/2/hi/science/nature/4566264.stm > > > > Also there was a study made by the UK microwave group (the body > representing > > UK amateur interests above 1GHz), which makes interesting reading. > It > > suggests that the signals from Galileo would have little impact > on > > terrestrial/EME 23cms opperation. Obviously the conclusions woule > require > a > > little re-interpretation, with respect to satellite based > reception. But > as > > Galileo transmissions will presumably be aimed at the earth, so > that any > > amatuer satellite will receive signals greater than that on earth, > for a > > minute part of it's orbit, I would think that the conclusions > drawn would > > still be valid. It's an interesting read: > > http://www.microwavers.org/papers/iaru/C5-13_Galileo.pdf > > > > Jules > > G0NZO > > > > > > >Speaking of allocations being taken away, I just can't fathom the > AMSAT > > >decision to drop L-Band up because of the "Galileo Affair." Now > that's a > > >decision based on "crystal ball engineering" and not fact. I've > even read > > >that if Galileo ever was launched - and that appears in the > latest press > to > > >be questionable" the US "would has threatened to shoot them > down!" > > > > > >Regards...Bill - N6GHz > > > > _______________________________________________ > > Sent via AMSAT-BB(a)amsat.org. Opinions expressed are those of the > author. > > Not an AMSAT-NA member? Join now to support the amateur satellite > program! > > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb > > _______________________________________________ > Sent via AMSAT-BB(a)amsat.org. Opinions expressed are those of the > author. > Not an AMSAT-NA member? Join now to support the amateur satellite > program! > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb > >

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S MODE OR NOT! here is my test results
by Luc Leblanc VE2DWE 11 Sep '06

11 Sep '06

On 8 Sep 2006 at 1:04, Tom Clark, K3IO wrote: > Yes, this decision was based on incomplete data. It would be wonderful > if many of you took the challenge to make quantitative measurements of > the S-band RFI levels in multiple locations. I try the test during the week end but i cannot received directly on 2.4ghz as i am using a downconverter and what i measure its the downconverter output. I was fortunate enough to find under a pile of paper a "test" sheet i made when AO-40 was at apogee with a squint angle of 8. I was writing at that time at elevation 0 a floor noise swinging between S-3 to S-5 on my Ft-847. I was concern at that time with the low elevation pass where i can be able to reach japan. What i hear was the usual pop pop but tweaking the DSP and the NB i reduce this QRM/N to a level where i was able to perform a QSO, and i made it i work Japan a couple of time then. At 25 degree of elevation the noise fell at S-1 and at 35 degree to 90 the noise remain at .5 S units. At that time The telephone and WI-FI interference was one of the main topics of discussion when speaking about U/S mode on AO-40. Over the week end i recheck my S band noise with EXACTLY THE SAME SETUP i was using in the above test. Did you know what i discover? EXACTLY the same results and AO-40 was placing a S6 to S9 signal at apogee with squint near 0. If AO-40 was still on i certified that i will able to replicate the same results without any doubts! The S2 TX power was about 100 watts and the antenna was only an helix of 8 turns if i can remember correctly. Even if Eagle delivers half this power with a cheaper antenna i am convince i will still be able to make it. You know my town was the fourth first erected in North America during the french regime. She's probably not the greatest in the world actually...but we have electricity and WI-FI and cordless phones who evoluate at the same pace as the other big towns on earth. This is real stuff from the real world and base on what i checked this week end i still don't believe the conclusions made about this FAKED noise problem. What they calculate it is an existing situation who was existing since 2003. Playing with carrier and large bandwidth receiver only confirm that during the whole life of AO-40 THE WHOLE WORLD succeed and quite easily to establish numerous CW and SSB contacts all over the world. This argumenting about a noise floor does not stand the road at all. Did they go fishing to see the reactions of the users? Did they want to force their own ways of thinking to the users or are they making some other clever tricks to as usual make the users swallow the sour pills? Be my guest and added your own explanation to my list. As you all know i develop during the recent years on this reflector a kind of carapace and i just give view an overview of what i received in this "trouble period":"I get emotional when people do not use the minds they have been given and allow people who are no longer even members of our organization drive a debate." I was always asking to restricts the posting privileges to MEMBERS ONLY when i was member but i was told by high ranking BOD members (could be the same he refer to)... that the AMSAT-BB is open to all... Sorry about this but i always believe the insulting comments are the arguments of the weeks or those who are making mistakes and who tries to cover them. Anyway i will protect the identity of this one but this bad planning by AMSAT-NA will only draw more and more members out. Will only remain those with political, financial, selfish interest. My only hope is they are not all in the president donor club... >From this on i suggest a motto for the October AMSAT symposium "WE WANTS S BAND DOWNLINKS ON EAGLE" As i am not a member i can only suggest it but i will try to update my web page to promote the motto. If S band downlink will be on eagle i will join the "gang" See you later S bander ;) "-" The medium is the message...The content is the audience...;) Luc Leblanc VE2DWE Skype VE2DWE www.qsl.net/ve2dwe

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Re: The Eagle has died.
by w7lrd＠comcast.net 11 Sep '06

11 Sep '06

Hello For me AO-40 was an "easy sat". A 30 inch primestar, helix feed, and a 3731 d/c. Only an occasional "click" from whatever. If we are looking at the sky with a dish, how does the higher noise floor and qrm from the ground affect our reception. I admit I am not quite understanding something. 73 Bob W7LRD Seattle -------------- Original message -------------- From: "Eric Van Offelen" <ericvo(a)telefonica.net> > Mode U/S with AO-40 was a real pleasure to work, with excellent signals once > the receiving set-up had been optimized (1.2 m solid dish and a good DB6NT > LNA). > Living here in high density WiFi area, cordless phones, wireless CCTV and > all kind of 2.4 Ghz junk ! > I could regularly hear the noise floor of the S band transponder and contact > very low power stations. > 73's > Eric > EA5GIY > > > ----- Original Message ----- > From: "i8cvs" > To: "Robert Oler" ; "Keith Bainbridge" > ; "AMSAT-BB" > Cc: > Sent: Sunday, September 10, 2006 2:52 PM > Subject: [amsat-bb] Re: The Eagle has died. > > > > ----- Original Message ----- > > From: "Robert Oler" > > To: ; > > Sent: Sunday, September 10, 2006 6:33 AM > > Subject: [amsat-bb] Re: The Eagle has died. > > > >> I sometimes look back on > >> the AO-40 Easy Sat articles (well written by Steve Ford) and smile. > >> > >> anyway intresting comments on your part. > >> > >> Robert Oler WB5MZO/portable > >> > >> Amsat Life member > >> Robert Oler WB5MZO Houston TX > > > > Hi Robert, WB5MZO > > > > In addition to the Steve Ford articles read please the article written by > > Antony Monteiro AA2TX in to QST september 2006 page-42 and smile > > again ! > > > > 73" de > > > > i8CVS Domenico > > > > > > > > > > _______________________________________________ > > Sent via AMSAT-BB(a)amsat.org. Opinions expressed are those of the author. > > Not an AMSAT-NA member? Join now to support the amateur satellite program! > > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb > > > > > _______________________________________________ > Sent via AMSAT-BB(a)amsat.org. Opinions expressed are those of the author. > Not an AMSAT-NA member? Join now to support the amateur satellite program! > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb

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P3E
by Tim Tapio 11 Sep '06

11 Sep '06

Can anyone point me in a direct for current status? I did some googling but couldn't find anything recent. Thanks! 73 de Tim, K4SHF FM04kx

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