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

ISS suit comms copied
by john heath 22 Feb '07

22 Feb '07

Hi, Listen on 130.167MHz FM (on old MIR frequency) for the suit comms during the Russian EVA. Good strong copy here over the UK at 15:30 UTC. Worth going onto the net and looking at NASA TV to check that the space walkers are still active before trying it. Good luck 73 John G7HIA

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Memorandum of Understanding
by Luc Leblanc 22 Feb '07

22 Feb '07

I remember a Post with this title "TOWARDS A TRUE INTERNATIONAL AMSAT" unfortunatly i lost the copy of it if someone can found this post and the author i will be glad to received a copy of it. Look like i speaking to myself again here but it's often the way i get the best answers Memorandum of Understanding between AMSAT-DL, AMSAT-UK and AMSAT-NA AMSAT-DL for the last five years has been building the P3-E spacecraft to be launched into a HEO and intended as a replacement for previous P3 satellites. It's purpose is to facilitate communication between radio-amateurs worldwide and at the same time to test and verify technologies and procedures needed for the P5-A mission to Mars. AMSAT-DL to this day has invested about 500,000 Euro into this project. AMSAT-NA and AMSAT-UK wish to contribute to the P3-E project, primarily with the goal to have the launch of P3-E as early as possible in order to give to their respective members the use of the communication services provided by P3- E. It is recognized that the capability of AMSAT-DL to raise funds limits the speed of the development of P3-E. In order to make a launch possible in 2008, AMSAT-DL has an immediate need of 40,000 Euro and an estimated need of ~200,000 Euro prior to the actual launch-date. AMSAT-NA and AMSAT-UK wish to help with the raising of these requirements by providing 30,000 Euro (AMSAT-NA) and 10,000 Euro (AMSAT-UK) in the near future. Furthermore, they wish to contribute by raising additional funding as the actual launch arrangements materialize. In order to achieve an effective cooperation in the funding effort and the construction and launching of P3-E, the following details to implement the cooperation are agreed: 1. The three AMSAT organizations will closely coordinate their activities and monitor progress of the project by frequent mutual consultations on the telephone. To this end the three parties will hold nominally a monthly telephone conference to review the status of the project and to identify problem areas. At this time the three organizations will be represented by Rick, Jim and Peter at these telephone-conferences. 2. According to need, the three organizations agree to hold sufficiently frequent meetings in person to review the project status. These meetings are assumed to be desirable with a frequency of 6-12 month between them. 3. It is understood by all three organizations that procuring a timely launch for P3-E is one of the bigger challenges of the project. AMSAT-DL is concentrating major efforts of procuring a launch with Arianespace, while AMSAT- NA is trying to develop a launch opportunity within the USA. All parties recognize that major progress in funding is contingent on a firm launch agreement. All parties further recognize that a timely construction and integration of P3-E is critically dependent on all parties giving highest priority to fulfilling their respective commitments. 4. All three organizations understand that funding progress is dependent on effective information dissemination worldwide. To this end the three organizations reiterate their mutual agreement that each organization can publish all P3-E related publications of the other two organizations in their respective public organs without special permission. Furthermore, each organization is free to prepare 'official' statements about the project, but these publications must be agreed with the project management of P3-E (AMSAT- DL) prior to publication. Requests for agreement to publish will be sent to Peter (or another person chosen by him), who will use best efforts to respond within 7 days with an answer. With other publications by individual authors no such agreement is necessary provided that the context makes it is clear that the publication is not an official declaration by the project management or AMSAT-DL. 5. AMSAT-DL reiterates that the operational use of P3-E will be primarily to provide amateur radio communication services. But all parties also understand that the spacecraft is a dual service satellite, and that AMSAT-DL retains the right to occasionally reduce the provision of amateur radio services if work towards P5-A requires this. A-DL will use due diligence to minimize the impact of the P5-A requirements on the provision of amateur services. For AMSAT-DL For AMSAT-NA For AMSAT-UK Peter DB2OS Rick W2GPS J Jim G3WGM "-" "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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TS790E mod
by Bill Ward 22 Feb '07

22 Feb '07

Dear All, Does anyone have any photographs/images (or a diagram) of the location of IC8 (for main RX) and IC1 (for sub RX) for 9600 baud modification of the Trio TS790. I don't have a complete set of circuit diagrams and don't want to mess it up! Thanks for your help. Regards, Bill. GM0ICF.

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Re: RAFT and ANDE speech callsigns
by Robert Bruninga 22 Feb '07

22 Feb '07

> How late will the command stations stay up at night > to activate the voice synthesizer on Ande? I have a > very timely and high EL pass over my location > (Southern CA) at 9:40 PM PST on 2/22 that I'd like to try... We only had one west coast command station, but he is on a long temporary assignment out of area, so we have command stations in California at this time. But I think I know of one I can ask and see if he is willing to operate these west caost passes when convenient. Command station needs a good OSCAR array on 2 meters for commanding. Bob, WB4APR > Robert Bruninga <bruninga(a)usna.edu> wrote: > > Now that ANDE and RAFT are both speaking, here are the > packet-to-voice synthesizer rules: > > 1) it turns the packet header into "XXXXXX says" > 2) it then speaks normal english and normal spellings.. > 3) It tries to spell CAPS, but we found that to force it to > speak a callsign correctly independent of starting character if > you make the second character a "!" then it will always speak > properly. Such as W!B4APR will be spoken as wb4apr as expected. > > Here are DK3WN and PE1ITR in packet-to-voice QSO: > > http://www.ew.usna.edu/~bruninga/ande/ande_11022007_2238.mp3 > > WB4APR, Bob > > ----original message----------------------------------------- > > RAFT is weaker, but speaks... > * if ANYONE has CONNECTED RAFT > * Then any APRS MSG to TALK will be spoken > > ANDE is stronger, but is lazy and sleeps unless woken up. > * ANDE must be awakened by 145.825 activity > * ANDE voice must be activated by command station each pass > * Then any APRS MSG to TALK will be spoken > > ANDE has better link performance for users, but needs command > stations, but you get more workable passses due to its better > links. > > For more info, see the ANDE-RAFT-OPS web page. > http://www.ew.usna.edu/~bruninga/ande-raft-ops.html > > Enjoy! > > Bob Bruninga, WB4APR > US Naval Academy Satellite Lab > > > _______________________________________________ > 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 > > > > ________________________________ > > TV dinner still cooling? > Check out "Tonight's Picks" > <http://us.rd.yahoo.com/evt=49979/*http://tv.yahoo.com/> on > Yahoo! TV. >

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Memorandum of Understanding
by Luc Leblanc 22 Feb '07

22 Feb '07

I remember a Post with this title "TOWARS A TRUE INTERNATIONAL AMSAT" unfortunatly i lost the copy of it if someone can found this post and the author i will be glad to received a copy of it. Look like i speaking to myself again here but it's often the way i get the best answers Memorandum of Understanding between AMSAT-DL, AMSAT-UK and AMSAT-NA AMSAT-DL for the last five years has been building the P3-E spacecraft to be launched into a HEO and intended as a replacement for previous P3 satellites. It's purpose is to facilitate communication between radio-amateurs worldwide and at the same time to test and verify technologies and procedures needed for the P5-A mission to Mars. AMSAT-DL to this day has invested about 500,000 Euro into this project. AMSAT-NA and AMSAT-UK wish to contribute to the P3-E project, primarily with the goal to have the launch of P3-E as early as possible in order to give to their respective members the use of the communication services provided by P3- E. It is recognized that the capability of AMSAT-DL to raise funds limits the speed of the development of P3-E. In order to make a launch possible in 2008, AMSAT-DL has an immediate need of 40,000 Euro and an estimated need of ~200,000 Euro prior to the actual launch-date. AMSAT-NA and AMSAT-UK wish to help with the raising of these requirements by providing 30,000 Euro (AMSAT-NA) and 10,000 Euro (AMSAT-UK) in the near future. Furthermore, they wish to contribute by raising additional funding as the actual launch arrangements materialize. In order to achieve an effective cooperation in the funding effort and the construction and launching of P3-E, the following details to implement the cooperation are agreed: 1. The three AMSAT organizations will closely coordinate their activities and monitor progress of the project by frequent mutual consultations on the telephone. To this end the three parties will hold nominally a monthly telephone conference to review the status of the project and to identify problem areas. At this time the three organizations will be represented by Rick, Jim and Peter at these telephone-conferences. 2. According to need, the three organizations agree to hold sufficiently frequent meetings in person to review the project status. These meetings are assumed to be desirable with a frequency of 6-12 month between them. 3. It is understood by all three organizations that procuring a timely launch for P3-E is one of the bigger challenges of the project. AMSAT-DL is concentrating major efforts of procuring a launch with Arianespace, while AMSAT- NA is trying to develop a launch opportunity within the USA. All parties recognize that major progress in funding is contingent on a firm launch agreement. All parties further recognize that a timely construction and integration of P3-E is critically dependent on all parties giving highest priority to fulfilling their respective commitments. 4. All three organizations understand that funding progress is dependent on effective information dissemination worldwide. To this end the three organizations reiterate their mutual agreement that each organization can publish all P3-E related publications of the other two organizations in their respective public organs without special permission. Furthermore, each organization is free to prepare 'official' statements about the project, but these publications must be agreed with the project management of P3-E (AMSAT- DL) prior to publication. Requests for agreement to publish will be sent to Peter (or another person chosen by him), who will use best efforts to respond within 7 days with an answer. With other publications by individual authors no such agreement is necessary provided that the context makes it is clear that the publication is not an official declaration by the project management or AMSAT-DL. 5. AMSAT-DL reiterates that the operational use of P3-E will be primarily to provide amateur radio communication services. But all parties also understand that the spacecraft is a dual service satellite, and that AMSAT-DL retains the right to occasionally reduce the provision of amateur radio services if work towards P5-A requires this. A-DL will use due diligence to minimize the impact of the P5-A requirements on the provision of amateur services. For AMSAT-DL For AMSAT-NA For AMSAT-UK Peter DB2OS Rick W2GPS J Jim G3WGM "-" "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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Effects of ionosphere in sat comms
by Paulo Pinto 22 Feb '07

22 Feb '07

Hi, I've been active in VHF/UHF LEO satellites for a couple of years now, after having spend many years around HF DX'ing. I always enjoyed sat operation since my first sat qso back in 1993 on RS-12 Mode K. One of my favorite subjects is propagation phenomena and I pay special attention to the VHF/UHF freqs. I pick as an example VO-52 satellite. The day before yesterday, on a 52 degree pass, I got very good downlink signals with my narrow and limited antenna setup: a fixed 9 elem TONNA at abt 30 deg. El. and 10 deg. Az. Yesterday, the same pass conditions gave me very poor reception. I understand that lack of satellite axis stabilization can be a high factor for this behavior, as the antennas may be turned around. But my question is: How severe earth's magnetic field and ionization of the atmosphere can affect Satellite Communications? If we must apply same theory as for ground communication, as logic suggests, what kind of refraction or dispersion may be associated with this epoch ? If don't know if this is a dummy question, but I would like to hear from those of you interested in this matters. 73 CT1ETE, Paulo

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Re: Could we raise orbit thru magnetorque?
by G0MRF＠aol.com 22 Feb '07

22 Feb '07

Hi all. I think we have all had fun looking at ways to raise an orbit and the answer seems to be, from the basic physics, that you will exert an extremely small force the effectiveness of which is dependant on the distance between the poles and the strength of the magnet, and some other things too However, to put this into perspective...........AO-51, which we all know and love, uses a similar principle for attitude stabilisation. Instead of repelling the space craft into outer space the magnet on board causes the spacecraft to rotate one turn per orbit. This ensures that over the northen 'pole' the antenna end of the spacecraft points straight down. Over the southern pole the antennas point in the other direction. (sorry southern hemisphere) - for those of us living between 50N and 50S it also allows us to predict whether we will get better signals (particually on 2.4G) as the spacecraft approaches or moves away from us. By knowing the attitude we know if the antennas are pointing towards us or not. Of course, what does not happen with AO-51 is that force of attraction from its magnet does not cause any measurable deteroration in the orbit. i.e. AO-51 does not show any tendancy to dramtically spiral down and crash into the earth. why? well imagine the forces involved. 1) you have the kinetic energy of a 20kg (?) spacecraft travelling at 18,000MPH. That's a lot of energy. - difficult to imagine....OK Just imagine 20kg hitting the side of your house at that speed....Yes, thats a lot of energy! compared to. 2) The force of a magnet with the poles 1 foot apart 1.5 million feet from the ground. Not sure if that helps. But it did make me understand how something with so much energy due to its velocity can be easily rotated on its own axis by a magnet, but not have its direction of motion changed by a that magnet. tnx David G0MRF In a message dated 22/02/2007 07:32:52 GMT Standard Time, ojwanga2(a)asme.org writes: The craft could push-off the magnetic field of the planet, using it as a rail. Andrew. KI4LTH/5Z4FT.

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Re: Could we raise orbit thru magnetorque?
by Marc Vermeersch 21 Feb '07

21 Feb '07

All, So why is the maglev principle (magnetic levitation) http://www.google.be/search?hl=nl&q=maglev&meta= not applicable in space? Magnetic levitation applied to trains generates an upward force equal and opposite to the earth's gravitation. BR, -- /\/\arc -----Original Message----- From: amsat-bb-bounces(a)amsat.org [mailto:[email protected]] On Behalf Of Bruce Bostwick Sent: Wednesday, February 21, 2007 6:51 PM To: amsat-bb(a)amsat.org Subject: [amsat-bb] Re: Could we raise orbit thru magnetorque? That's been my understanding as well. Magnetorquing by itself can drive rotation but not translation. Its main benefit is that it saves propellant, weight, and complexity, as well as moving parts and the risk of a hypergolic plumbing assembly exploding and taking out half the spacecraft's systems, by allowing the spacecraft to handle rotation with more reliable torquing coils and get its energy for that from the PV panels. Changing orbits still requires firing a reaction thruster of some sort. On Feb 20, 2007, at 9:47 AM, John Mock KD6PAG wrote: >> Argument is: if when satellite is in the north, a north magnetic >> field is >> applied on z plane, will satellite raise orbit ? Same but opposite >> on south. >> Considering limited energy available could this raise be >> significant if >> applied on all orbits ?. > > I believe magnetorquing can only change the orientation of a > satellite and > not its orbit. It is certainly used in the process of changing an > orbit, > in order to get a thrusting device pointing in a direction where it > will > do something useful. But by itself, it can't change an orbit. It > can help > point antennas in the proper direction, etc. > > -- KD6PAG (Networking Old-Timer, Satellite QRPer) "People don't like to be meddled with. We tell them what to do, what to think, don't run, don't walk. We're in their homes and in their heads and we haven't the right. We're meddlesome." -- River Tam, "Serenity" _______________________________________________ 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: Advice on antennas for working the LEO's
by TOFFY 21 Feb '07

21 Feb '07

>The other aspect I'm wondering about is cross polarization losses, >the way that I plan to have it configured is with the 2 meter section >horizontal and the 70 cm vertical. So would that be significant for the LEO's? Dear Gary and All I have use . A homebrew antenna 2 Band on same boom. 2m. band is 5ele. Horizontal and the 70 cm. 9ele. vertical on boom length about 1.7 m. Have distance 0.5m. between 2 Driven element.(1/4 lamda on TX band) Base Design each band from DK7ZB Yagi antenna. A boom is elevation-Lock at 15 degree and use only azimuth rotator. antenna height about 5 m. I can use AO-51,FO-29,ISS,RAFT,ANDE,AO-7(mode-A only) ,VO52(RX only) and monitor all CW Cube-sat at NOT over 40 degree elevation. Signal have QSB on FM satallite. Sometime can work low to 3 degree elevation. At high elevation I switch to use Moxon on 2m. and Quadrifilar Helicol on 70cm. 73s de Toff HS0NNU ____________________________________________________________________________________ Yahoo! Music Unlimited Access over 1 million songs. http://music.yahoo.com/unlimited

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AMSAT-BB
by Mr Jeffrey Ross 21 Feb '07

21 Feb '07

HI ALL, OK GREAT NOW BACK TO THE SATS I SEE GREAT, HI WHATS THE HAM MOTTO AGAIN? MAYBE THAT SHOULD BE POSTED HERE ONCE IN AWHILE. KC8GKF

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