July 2009 - AMSAT-BB - mailman.amsat.org

Re: The Moon is our Future
by Armando Mercado 02 Jul '09

02 Jul '09

Greetings, Not to be a wet blanket, but what is the advantage of an amateur repeater on the moon? >From a mid-latitude location, the moon is above the horizon 8.5 to 16 hours per day depending on the season. The repeater would be in darkness and presumably un-powered for 2 weeks each month. Even if it was located in a permently illuminated point near the poles, librations would take it out of view of earth at times. Link margins would be large, but not insurmountable. Designing a comm package to survive the temperature extremes would be difficult but not impossible. The US and USSR had unmanned landers that survived many lunar day night cycles. We do have experience flying amateur repeaters on manned space missions. There's one on the ISS right now. It is turned off on a regular basis because of crew time availability and flight safety rules. One can only imagine what constraints would be imposed with a comm package on the moon. There would be many technical, logistical and financial challenges for a lunar amateur repeater to overcome...and all from an international organization that has yet to replace AO-40. 73, Armando, N8IGJ >Date: Thu, 2 Jul 2009 04:31:45 -0700 (PDT) >From: MM <ka1rrw(a)yahoo.com> >Subject: [amsat-bb] The Moon is our Future >To: kg4zlb(a)gmail.com, amsat-bb(a)amsat.org, "Jack K." ><kd1pe.1(a)gmail.com> >Message-ID: <878811.97851.qm(a)web56408.mail.re3.yahoo.com> >Content-Type: text/plain; charset=utf-8 >Theoretically we may have a free ride to the Moon for an Amateur radio >repeater!

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Chinease sat any news?
by Luc Leblanc 02 Jul '09

02 Jul '09

>From my archives did any one get fresh news about this Chinease sat? SB SAT @ AMSAT $ANS-279.02 October 4 2008 First Chinese Amateur Radio Satellite to be launched in June 2009 AMSAT News Service Bulletin 279.02 From AMSAT HQ SILVER SPRING, MD. October 5, 2008 To All RADIO AMATEURS BID: $ANS-279.02 Michael Chen, BD5RV/4, reports that he recently received an update from Alan, BA1DU, on the progress of the first Chinese amateur satellite. Things are now going smoothly. This satellite was formerly named CAS-1 and is now XW-1. It carries a beacon and three cross band transponders: FM, linear, and digital. The satellite is planned to be launched into a Sun synchronous orbit in June 2009 by a CZ-2C rocket in Taiyuan Satellite Launch Center in North China. [ANS thanks Michael, BD5RV/4, for the above information] /EX "-" Luc Leblanc VE2DWE Skype VE2DWE www.qsl.net/ve2dwe WAC BASIC CW PHONE SATELLITE

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I: How you do DOPPLER correction in Linear Transponders?
by Francesco Grappi 02 Jul '09

02 Jul '09

Hi Fabiano, In my opinion for sure keep fixed downlink frequency and adjust uplink frequency. So on this way you don't "slip" on the transponder downlink..... 73 Frank IW4DVZ -----Messaggio originale----- Da: amsat-bb-bounces(a)amsat.org [mailto:[email protected]] Per conto di Fabiano Moser Inviato: giovedì 2 luglio 2009 18.20 A: amsat-bb Oggetto: [amsat-bb] How you do DOPPLER correction in Linear Transponders? Dear friends, We know that some Satellite Operators use diferent system to doppler control. For Linear Transponder 1) Adjust uplink and downlink automatic by CAT? (Not always woks, some times I´m up or down from the computer adjust) 2) Adjust uplink and downlink manual 3) Keep Uplink fixed and adjust only the Downlink frequency. What is the more indicate method to use? FT-847 have knob to adjust Uplink without change downlink VFO, and I´m using it to keep my voice in downlink at same downlink much I can. But I know some operators use fixed uplink. How you do? -- 73 Fabiano Moser CR7/PY5RX ARISS-PORTUGAL (Amateur Radio on the International Space Station) Representative at Teleconference and Portugal Telebridge Coordinator. AMRAD/AMSAT-CT http://www.amrad.pt/ariss.php "There is no great talent without great will. (Honoré de Balzac)" _______________________________________________ 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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Re: The Moon is our Future
by David - KG4ZLB 02 Jul '09

02 Jul '09

OK, I just love conspiracy theories :-D Are you really Michael Moore ? :-D kd8bxp(a)aol.com wrote: > I don't think man will ever walk on the moon. And I really didn't want to start a whole thing on this - > Someone said that a man would have to roll out an antenna for a amatuer project - I just don't think that will ever happen > A small robotic rover could do it but then you are talking expensive unless nasa was willing to give "us" time on a rover that was going to do experiments for nasa > > LeRoy, KD8BXP > http://www.HamOhio.com >

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Re: The Moon is our Future
by Robert Bruninga 02 Jul '09

02 Jul '09

> But doesn't it have to be above ground? > Yes the moon is dry and probably the > poorest conducting dirt there is, But > just like on Earth it can't be laying > on the ground yes? Good question... Even if the ground was a perfect reflector and conductor, then the antenna would only have to be 19" above the ground at 2 meters. Next consider that the moon is rock and extremely dry... And rock has about 1/1000 the conductivity of moist soil... So where the "true" reflection in the ground of the moon is surely many feet down. So sitting it on the ground" of the moon is probably 99% as effective as trying to hang it 19" up. > Robert Bruninga wrote: > > > BUT one easy way to get gain is to use just a long coaxial gain > cable. I think it takes about 22 feet of coaxial dipole > elements at 2 meters to give about 6 dB of gain. So laying down > 6 dB gain segments on the rock of the moon is as easy as > unrolling a spool of cable. Unrolling 8 of these with the right > spacing could yield about 17 dB. > > Of course this woiuld only point straight up, so it would need > to be on a moon base in the middle of the earth facing side. > But since there is a lot of interest in moon bases near the > poles where there might be water, then a similar array of layed > down coaxial cable arrays could be phased horizontally to point > at earth. Actually, just about any direction can be obtained > with the right spacing. > > ONLY problem of course is there has to be someone with legs to > roll out the cables. > > Just a thought. > Bob, WB4APR > > > ________________________________ > > > > No virus found in this incoming message. > Checked by AVG - www.avg.com > Version: 8.5.375 / Virus Database: 270.13.2/2214 - > Release Date: 07/02/09 05:54:00 > > > >

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Re: The Moon is our Future
by David - KG4ZLB 02 Jul '09

02 Jul '09

Just a question but if you do not think the US got to the Moon in 1969 and neither do you think they will get back to the Moon in 2012, how do you propose seeing an amateur repeater on the Moon? Get the crew of the ISS to toss out a repeater, like SuitSat, but throw it really, really hard in the general direction of the Moon and hope it lands? I don't understand your logic. 73 David KG4ZLB kd8bxp(a)aol.com wrote: > Don't want to get a whole new thing started here but - I don't think we ever went to the moon in 1969 and I don't think we will ever goto the moon - in 2012 or whenever they proposed a "return" to the moon > > I would love to see an amatuer repeater on the moon thou - from my understanding EME is expensive to do, so I think it would leave most of us out > > Where as and bringing things back around - LEOs are realitive low cost to use to the normal everyday day > > I will put my two cents in for more LEOs - :-) > > Hey are there any geosynchinze amatuer sats up? > > LeRoy, KD8BXP > http://www.HamOhio.com > -

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Re: The Moon is our Future
by MM 02 Jul '09

02 Jul '09

Of course, lets get more Universities involved and build more Leos satellites to fill those small ballast spots on new satellites. The Moon option could be cheaper than a HEO's, if we can get it in as Public Relations NASA project. The cost to get a ride on a HEO satellite is multiple millions just for the ride into space. Amsat paid over a million dollars just to ride a Prototype Rocket (AO-4). If you want to ride a Non-prototype rocket to high orbit, add another 20 million. Cheap High orbit rocket rides are few and far between. The Moon is the most affordable ride option this decade. 20 years ago NASA was looking for ballast for the TDRS satellites. We had the opportunity to put a ham project on a few GEO satellites and missed the opportunity. Lets not miss the Moon. http://www.marexmg.org/fileshtml/ArissRebuild.html --- On Thu, 7/2/09, David - KG4ZLB <kg4zlb(a)googlemail.com> wrote: > From: David - KG4ZLB <kg4zlb(a)googlemail.com> > Subject: [amsat-bb] Re: The Moon is our Future > To: amsat-bb(a)amsat.org > Date: Thursday, July 2, 2009, 11:15 AM > On the contrary, we need more LEO's > to augment and replace the existing > aged fleet. > > Whilst AMSAT works on the HEO's lets put some of our > efforts towards the > Universities who seem to regularly put up 2/70 satellites! > > -- > David > KG4ZLB > www.kg4zlb.com > > > > Jack K. wrote: > > I heard the same things when the first HEOs went up. > It takes to much > > money, it takes to much specialized equipment, it > takes to much > > knowledge, it is for elitists only... The bottom line > is a LOT of hams > > used them and it took some ingenuity, some new > equipment, and yes we > > all had to learn now things to use them. the bottom > line is they > > worked and worked well... My suggestion is quit > looking at pitfalls > > and problems as reasons not to do something, but as > opportunities to > > learn to accomplish new things (or improved > communications anyway) and > > move forward... We can put up all the leos we want, > but until someone > > makes something like B. Bruninga's cell concept work, > we are only > > going to have more of the same, We don't need more of > the same! > > > > DE - KD1PE > > > > > > ----- Original Message ----- From: <kd8bxp(a)aol.com> > > To: <bruninga(a)usna.edu>; > "'Joe'" <nss(a)mwt.net>; > "'MM'" <ka1rrw(a)yahoo.com> > > Cc: "'Jack K.'" <kd1pe.1(a)gmail.com>; > <amsat-bb(a)amsat.org>; > > > <kg4zlb(a)gmail.com> > > Sent: Thursday, July 02, 2009 8:28 AM > > Subject: Re: [amsat-bb] Re: The Moon is our Future > > > > > > > > > > _______________________________________________ > 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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[Fwd: Re: Re: The Moon is our Future]
by n0jy＠lavabit.com 02 Jul '09

02 Jul '09

Somehow I sent this in reply to Bob instead of the group. Sorry, Bob. > BUT one easy way to get gain is to use just a long coaxial gain > cable. I think it takes about 22 feet of coaxial dipole > elements at 2 meters to give about 6 dB of gain. So laying down 6 dB gain segments on the rock of the moon is as easy as > unrolling a spool of cable. Unrolling 8 of these with the right spacing could yield about 17 dB. > > Of course this woiuld only point straight up, so it would need > to be on a moon base in the middle of the earth facing side. > But since there is a lot of interest in moon bases near the > poles where there might be water, then a similar array of layed > down coaxial cable arrays could be phased horizontally to point > at earth. Actually, just about any direction can be obtained > with the right spacing. > > ONLY problem of course is there has to be someone with legs to > roll out the cables. How about, if the location is very near the pole, an array that extends up like a push-pole vertically from the craft, with tape measure type dipoles that spring out horizontally when the pole goes up? You might need a small rotator on the base of the pole then to make sure the dipoles point at Earth depending on the orientation of the craft when it lands, but that would only need to be turned once I believe, when it is deployed. Jerry N0JY

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Re: The Moon is our Future
by MM 02 Jul '09

02 Jul '09

Dear Jack: Thank you for your great comments. Let’s find the problems and find the solutions. We solved the difficulties for working AO-10 and AO-13. The Moon is the Next Generation. Lets work together to find an affordable solution. Which band will work the best (assuming limited antenna and power recourses from an Un-manned Moon lander.) The Moon will not be an “Easy-Sat”, it will be a challenge. However, it should be much easier to access than true EME. Thanks all Miles WF1F MarexMG.org --- On Thu, 7/2/09, Jack K. <kd1pe.1(a)gmail.com> wrote: > From: Jack K. <kd1pe.1(a)gmail.com> > Subject: Re: [amsat-bb] Re: The Moon is our Future > To: kd8bxp(a)aol.com, bruninga(a)usna.edu, "'Joe'" <nss(a)mwt.net>, "'MM'" <ka1rrw(a)yahoo.com> > Cc: amsat-bb(a)amsat.org, kg4zlb(a)gmail.com > Date: Thursday, July 2, 2009, 8:48 AM > I heard the same things when the > first HEOs went up. It takes to much money, it takes to much > specialized equipment, it takes to much knowledge, it is for > elitists only... The bottom line is a LOT of hams used them > and it took some ingenuity, some new equipment, and yes we > all had to learn now things to use them. the bottom line is > they worked and worked well... My suggestion is quit looking > at pitfalls and problems as reasons not to do something, but > as opportunities to learn to accomplish new things (or > improved communications anyway) and move forward... We can > put up all the leos we want, but until someone makes > something like B. Bruninga's cell concept work, we are only > going to have more of the same, We don't need more of the > same! > > DE - KD1PE > >

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Re: The Moon is our Future
by MM 02 Jul '09

02 Jul '09

Hello Joe: Thank your comments. My EME experience is minimal. I have only been able to hear a few signals from the Moon and have yet to complete a full 2-way EME (new antenna in progress). I am sure there are some people on this emailing forum that have more experience than I have with EME communications. The reason for a small antenna setup on the NASA lander proposal is because I believe it will be harder to convince NASA to allow us to install a 20 foot boom on the lander. Right now this is the concept theory phase. Is a 2m/440 SSB transponder practical? If our analysis proves that it is not, then we can move on higher in frequency until we find an affordable solution (within the ITU guidelines). The ground stations will need to be Oscar class or better (12-15+ dBd). The question is, which frequency combination will give us the best bang for the buck and provide access to the most users? A Moon repeater will never be accessible via a HT. And with the exception of one (1) truck I saw, it will not be accessible to mobile SSB systems. --- On Thu, 7/2/09, Joe <nss(a)mwt.net> wrote: > From: Joe <nss(a)mwt.net> > Subject: Re: [amsat-bb] The Moon is our Future > To: "MM" <ka1rrw(a)yahoo.com> > Cc: kg4zlb(a)gmail.com, amsat-bb(a)amsat.org, "Jack K." <kd1pe.1(a)gmail.com> > Date: Thursday, July 2, 2009, 9:20 AM > > > MM wrote: > > > Theoretically we may have a free ride to the Moon for > an Amateur radio repeater! > > > [snip] > > > > > > > One theory: > > We need a simple Mode-J transponder (2-meters up, 440 > down). > > Low power consumption. > > Assume minimal antenna gain from the Lander (3 dBd on > each antenna) > > Assume transmitter power 5-10 watts. > > > > > Why go with the minimal antenna gain? From the moon > the whole Earth only displays less than 2 degrees in the > sky. ( Moon shows 0.5 degrees from earth) > Why spill all the power where people are not? > > In addition, once the antennas are positioned, > that's more or less it. There is a slight wobble > (Libration) of 6.5 degrees So any antenna with a > 3 db point that exceeds 6.5 degrees is just wasting > transmitter power. > > And with this link budget even an active bird that has > landed and not flying it still will need some pretty hefty > power to not need a major antenna setup on the earth side of > the system. > > Just remember what an Oscar 10 station took to have > reliable communications,, At Apogee it was only 35,000 > miles away, the Moon is almost a ten fold > increase in distance, to keep the lander from having > to run hundreds of watts to be heard on the earth, > ever DB of antenna gain will be needed for sure! > > Joe WB9SBD >

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