February 2007 - AMSAT-BB - mailman.amsat.org

Re: Earths Magnetic Field strength
by Patrick McGrane 21 Feb '07

21 Feb '07

Greetings- I wont bother with your disinformation and please dont take my writings out of context. You must use a blackberry or something, your like a hawk on the BB. Bye Bye, pat n2oeq Everyone else; always look at the basic ideas or the "big picture" ------- Original Message ------- >From : Robert Bruninga[mailto:bruninga@usna.edu] Sent : 2/21/2007 9:34:44 AM To : amsat-bb(a)amsat.org Cc : Subject : RE: [amsat-bb] Re: Earths Magnetic Field strength > I moved a handheld compass towards a heavy... speaker magnet. > When the compass was a few inches away from the magnet, > it changed direction from North to the direction of the magnet. As someone else pointed out earlier, that is because of the gradient or difference in "force" on one end versus the other. One end of the compass was an inch or so closer to one pole of the magnet than the other end. But in space, the pole of your spacecraft magnet that you are trying to repel, is only one foot closer to the Earths pole, than the other pole which is attracted. So the difference in distance of the force that is pulling to the one that is pushing is only 1 foot out of say 21,120,000 feet to the Earth's pole. Hence the net force difference is a 21 millionth SQUARED or .00000000000004 of the force that you observed on the compass. Or something like that. Bob _______________________________________________ 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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Report on Echo in the Middle School Classroom
by Bruce Robertson 21 Feb '07

21 Feb '07

Gang: After two mornings of teaching a total of three 50min classes, I can say that a presentation based around AMSAT activities (and Echo specifically) works very well at the 6th grade level. However, the students were already engaged in a science curriculum regarding basic aeronautics, astronomy and planets, and they were about to discuss satellites to a greater or lesser degree in the coming weeks. After an introduction to the idea of a satellite and their uses, the bulk of my presentation centered around the design, building and journey to launch of Echo. I'm afraid I pillaged Bill Greene's on-line photo archive. (Students always love the one of Echo strapped into its own seat aboard the plane to Kazakhstan.) Then I prepped them to listen to a short QSO between myself and David EB4DEH, who kindly sent me a mp3 a year ago. For today's class I arranged with a local ham to have them do an satellite-style contact over a local repeater (giving callsign and gridsquare). Unfortunately, I wasn't able to alert him that the schedule had changed. Nevertheless, the students were interested by the repeater's response, and I could show that it was much like the equipment on-board Echo. Finally, I talked about some Cubesat projects, including Genesat and the upcoming CanX-2, of special interested due to its Canadian origin. Surprisingly, to me at least, Cubesats seemed to resonate with them. (My daughter, who was in one of the classes, confirmed this impression by listening in to later conversations.) I think their simplicity appealed, as well as the fact that these were made by university students on a budget. I'd say these presentations went well, even though we never listened to a satellite live. Something to consider if the technical challenges of doing a live demo seem to daunting. In effect, your experience and enthusiasm will carry the event. It should be said that I am a university professor and used to working in the classroom (though my teaching is in the Humanities). Nevertheless, this age group warms quickly to the guest speaker and is easily impressed by the cool stuff. While the teachers involved thanked me profusely, I think I should pass on their gratitude to the AMSAT community for providing such an engaging basis for education. And to think that they never even spoke over the bird! I have some recommendations for AMSAT based on this experience. First, a more extensive set of free-to-use educational diagrams would be very useful and, I think, an excellent recruitment tool. They would probably find their way onto Wikipedia and other places, with a reference to AMSAT. There may be more than I think already available: the AMSAT website was briefly and uncharacteristically unavailable when I was working on the presentation on Sunday night. More ambitiously, I think we should consider establishing the infrastructure for a network of Middle or High Schools clubs or classrooms who are affiliated with the cubesat and APRS satellite initiatives and have stations that feed them data. What sort of infrastructure? There's two important components I can think of. To my mind what matters here from the school's and students' perspectives is kudos, recognition from a larger group. If this is so, CalPoly or some other institution could produce some certificates recognizing Ms. Smith's class in Podunk Hollow, NB as a "Member of the International Satellite Collective" or what-have-you. Make a website, and list the participating schools for each year. Ms. Smith feels (rightly, mind you) that she's done something to make her class part of the larger world, and her school administration has something to brag about, too. Participation would be determined by submitting telemetry, simple as that. If the CAPE people are thinking of engaging local schools, they might consider how much little greater effort it would take to globalize the effort, seeding cubesat stations around the world. Bob's Navy lab would also be a great place for this. The other component of such a job would be to streamline and automate the collection and dissemination of telemetry. I'm working on a Jabber project that does this; stay tuned for more. 73, Bruce VE9QRP

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Greetings from a new op - help me wet these feet
by Jonny 290 21 Feb '07

21 Feb '07

Hi, KC4YLV here and it's been a dream of mine ever since I was a young kid to get on the amateur satellites. Well, close to two decades later and I can finally start dabbling with it. Can anybody give me a primer as to what the hottest satellites are right now? It unfortunately seems as though a lot of the info on the amateur satellites is outdated or at least 2, more often 5 years ore older. Given the lifespan-limited nature of our precious birds, it's really tough for me to figure out just what's still operating and what's gone. The mailing list seems dynamic and gives me hope - I know Amateur Radio is declining somewhat and wanted to be reassured that the birds are still being used and experimented with. I have 40 watts of all-mode 2m TX, 55 watts of 2m/70cm FM TX, and extra receivers (unfortunately I do not have 435 SSB capability but am working on that angle presently). I'm also set up for packet via MixW and can build whatever interfaces I'd need for that angle - I am quite interested in playing with digital modes. I've found plans for 'eggbeaters' and 'texas potato mashers' and feel that I would like to get started with omni antennas before I worry about gain antennas and tracking. Am I going to have enough ERP to have fun, or will I just be disappointed? Also, can anybody clue me in to the status of any high orbit or molniya satellite projects? the phase 3e pages seem to be dormant, have conflicting, or sometimes incorrect info. 73, Matt KC4YLV em26

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Earths Magnetic Field strength
by Patrick McGrane 21 Feb '07

21 Feb '07

Greetings to the group. I Thought the argentinians idea of using the magnetic field for propulsion was a great one! Let me share a simple experiment with you; Back in the late 80's I tried a simple experiment, I moved a handheld compass towards a heavy 10 ounce speaker magnet. When the compass was a few inches away from the magnet , it changed direction from North to the direction of the magnet. I think this illustrates that the earth's magnetic field is very strong, not weak. Try it yourself, then use your imagination. 73, pat N2OEQ

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Advice on antennas for working the LEO's
by Gary McKelvie 21 Feb '07

21 Feb '07

Hi to the List, My names Gary, I'm just getting started in the sats, initially looking to work the LEO's with FO 29 in particular. The station is going to consist of a Yaesu FT 847 cat controlled by Ham Radio Delux to control the radio for Doppler. It's suitable antennas that I have a problem with from web pages etc a lot of people seem to use the arrow antenna, which unfortunately as far as I can see is not available here in the UK. There is an antenna by Tonna which is a 9 element on 2 and 19 element on 70 claimed gain is 13 dBi on 2 16 dBi on 70. The feed line I will be using to get to the antenna will be a short run of West Flex 103 (which is half the loss of RG 213) I'm hoping to avoid the use of pre amps if possible as getting power to them is a problem. This antenna set up will be temporary in nature, with it being set up each time it is in use. I will be able to rotate the antenna in azimuth by hand or using a azimuth rotator. So would this setup work? So really all I'm not sure is how effective this setup will be and am looking for ideas and suggestions. Regards Gary G7USC Gary McKelvie G7USC Web : www.garym.org.uk Mobile : +447968501863 MSN Messenger : gm7usc(a)hotmail.com So Long and Thanks for all the Fish

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Re: US launch vehicle history [was: Re: Godwin's law]
by Edward Cole 21 Feb '07

21 Feb '07

At 02:17 PM 2/20/2007, Margaret Leber wrote: > From: Patrick McGrane [mailto:N2OEQ@aceweb.com] > > > The US brought Werner Von Braun here to the US to design rockets > > which included the Atlas 5. > >Check your history. Von Braun worked on Redstone and >Jupiter/Jupiter-C, since he was working for the Army. The original >Atlas was the work of Karel Jan Bossart (who came to the US from >Belgium in 1930), and was a USAF project. Von Braun left the Army to >work for NASA at Marshall in 1960, where he led the Saturn program. > >Atlas 5 was a *much* more recent program, it even came after Atlas II. >The first Atlas 5 flight was in 2002. > >Folks who read all of the thread in question know who *actually* >busted Godwin's Law first. :-) > >-- >73 de Maggie K3XS >Editor, Phil-Mont Mobile Radio Club Blurb - http://www.phil-mont.org >Elecraft K2 #1641 -- AOPA 925383 -- ARRL 39280 He probably meant the Saturn-5 which was used on the Apollo missions. If any of you were old enough to have watched TV back then, you would have seen the repeated series of failed (US Navy) Vanguard attempts to launch an orbiting package. Only, after The Jupiter-C team was allowed to launch (they had petitioned to do this for months), then the US succeeded in orbiting a satellite. Von Braun's groups main contribution was helping the US in the missile race with the USSR. The USSR imported their own German rocket experts for their program. The only folks with launch capability were the military. NASA provided the satellite and mission organization. Many of my former colleagues at JPL worked on the tracking system. My room mate (we shared an apartment on the calif. beach) worked in Orlando on the Saturn. 73, Ed - KL7UW ====================================== BP40IQ 50-MHz - 10-GHz www.kl7uw.com 144-EME: FT-847, mgf-1801, 4x-xpol-20, 185w DUBUS Magazine USA Rep dubususa(a)hotmail.com ======================================

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IC-910H + WispDDE Users
by Matt Bennett 21 Feb '07

21 Feb '07

Hi All, Does anyone use this radio and software control combination for same-band operations (like ISS)? I was curious if you were able to tune both the Main and Sub-Band frequencies within the same band and xmit/recieve like normal w/o full duplex operations. If so, what mode are you in when performing these operations (split, sat)? Thanks, Matt Bennett KF6RTB Matt Bennett KF6RTB UCISAT Communications Team Member University of California, Irvine www.ucisat.net --------------------------------- Never Miss an Email Stay connected with Yahoo! Mail on your mobile. Get started!

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censorship or lost mail
by Patrick McGrane 21 Feb '07

21 Feb '07

It appears one of my emails in reply to a snippit response has not made it through. Is This BBS censored or should I try again.? Pat N2OEQ

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Signal to Noise ratio
by John K9IJ 21 Feb '07

21 Feb '07

Well, the noise to signal ratio here has risen to the threshold of pain. I have better things to do with my (limited) time. Maybe I'll come back in a year and hope that members are talking about satellites again. Sad, very sad..... - John Rice K9IJ k9ij(a)vx5.com Long time Life Member of Amsat

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Delete key and filter TEST
by Luc Leblanc 21 Feb '07

21 Feb '07

Just to remind you my very first post subject... AMSAT-NA should not let AO-51 satellite in the hands of an army wing. As all amateur radio satellite they should be used for amateur radio operation not for any military use. For those who are discussing about a way to control satellite attitude by magnetorquing don't try to use the intelligence level from some on this BB as if we added the sum of all of this energy i think we will not have enough power to drive a RL5-W10015. I even think some a former US soldiers!!! With so many who are supposed to have their filter on on me they are apparently a bunch of liars... they probably lick the boots of their army chief to much! There is also no need to copy and copy and recopy or repost my posts. You will only added to the general confusion and mixed up as it was proven that some are actually under severe depression it will be advisable to let them relax in peace if we still want to enjoy them and their legendary stupidity. We are not born stupid and dummy we became it! Correct me if i'm wrong I hope :)) Here is some excerpt from the messages i received i start my 10 hit list but i have enough stuff to make about 10 list and some can throw you out of your socks... Viva Cuba El territorio libre en el America y Patria o muerte. (para compagneros y compagneras commentarios) 10- Can't you be little original or is that past your adult educational level which is probably first grade? 9- You poor brainwashed simple minded ignorant moron. 8- I'm an american citizen who is disappointed that Americans drafted Werner Von Braun of Nazi fame to design the atlas 5 rocket for the appollo 7- You must be some kind of government or military axe man. Funny how the ideas presented seem to be attacked with ignorant one-liners. Kind of like Planet of the apes movies 6-What's funny on this BB is many are interpreting the text with what they think silently. Probably afraid to be honest up to a point to reveal what they really think about "real questions" 5-we have issues around the world where other nations, races and bodies believe that if one will/shall all will/shall. 4-Mr Davies- I enjoy seeing posts from luc 3-I may not agree with all that Luc and others post but they have every right to express their opinions with the proviso that what they post does descend into open personal abuse. 2-Ed: You are exactly correct, I would like to apologize to you and the BB for my replies to Luc. 1- And the CIA and US Military have been acting without Conscience or impunity since 1950 - EVERY SINGLE MAJOR CONFLICT Was a result of LIES and deception for power, greed and corruption. Cha cha cha! "-" "It is not the class of license the amateur holds, but the class of the amateur that holds the license." Luc Leblanc VE2DWE Skype VE2DWE www.qsl.net/ve2dwe WAC BASIC CW PHONE SATELLITE

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