December 2008 - AMSAT-BB - mailman.amsat.org

Re: ARISS antennae
by Bob Bruninga 30 Dec '08

30 Dec '08

>> Still haven't found what beam width >> and direction the antennas view >> from the ISS WRT its direction of flight. > ...In either case, they are considered > to be on the earth-facing surface... Actually, an "earth facing" antenna can be confusing to some. Because only about 5% or less of the earth bound users that are in view are "under" the ISS. Whereas 95% of them are to the side in all directinos most of the time. In fact, almost 70% of them are within just 20 degrees of horizontal in all directions from the ISS. So, a "down" antenna with any gain, is not the ideal spacecraft antenna. See the plot of elevation angle versus distance and time in view on this web page: www.aprs.org/rotator1.html That sketch is shown from the perspective of the ground station, but just turn it upside down, and you see that almost all communications to the ISS are "from the side"... Good luck! Bob, Wb4APR

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ARISS antennae
by Alan Sieg WB5RMG 30 Dec '08

30 Dec '08

WA4SCA asked : > Still haven't found what beam width and direction the antennas view > from the ISS WRT its direction of flight. >> > I know this is out there, but does anybody have off the top of their head > a reference on the ISS antenna orientation, and what its view is WRT the > direction of flight? Which sent me on a brief scavenger hunt ... with these quick results. Description (new one is probably available somewhere) of ARISS antenna (2002): http://spaceflight.nasa.gov/station/reference/radio/antennas.html (You can click on the pictures for hi-rez views) The WA1 and WA2 antennae are reportedly on the perimeter of the Zvezda module, on the nadir (earth-facing) side, near the Soyuz docking port.?. These appear to be of the flexible spring element type for VHF & UHF, with a patch-type for L & S band. These also support Russian spacewalk video. The WA4 antenna reportedly has an element for 10 meters instead of VHF. A very detailed description of antenna development effort for Columbus Lab : http://www.ariss-eu.org/columbus.htm I don't now if these recent tests are with these new Columbus antennae or the existing elements on the Russian segment. I'm guessing the originals. In either case, they are considered to be on the earth-facing surface... Perhaps ARISS team personnel can enlighten us further, with links... Thanks /;^) -- <- Licensed in 1976, WB5RMG = Alan Sieg * AMSAT#20554 -> <- http://www.somenet.net * http://wb5rmg.somenet.net -> <- http://www.linkedin.com/in/alansieg * My 'Day Job' ->

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ISS Repeater
by n1jez＠burlingtontelecom.net 30 Dec '08

30 Dec '08

Just got on the ISS repeater - L band up and V band down from FN34 here in Vermont. I used full power here. 80 watts in the shack to a 55 el 1269 Directive Systems loop yagi. Transmission line is 75' of 7/8" hardline. Results were mixed. The pass was 25 degrees max here. I had little to no success as the ISS was ascending. I opened the repeater a couple of times. I'm not sure if this was because other stations were trying and we were clobbering each other or not. As the ISS was going overhead, it appeared that the polarity was shifting rapidly as I would open the repeater for just a word or two. I did hear Clare, VE3NPC briefly. As the ISS was descending, things got better and I was able to consistently open the repeater, but nobody came back.... I could not access the repeater below 10 degrees.... If anyone else was on and trying, can you let me know? I'd like to see if that was the reason I couldn't access the repeater as it was ascending. One other observation, I found the doppler correction to be pretty critical. I've seen this when running low power into AO-51 for tests. I hope to try a few more passes this week. 73, Mike, N1JEZ AMSAT 29649 "A closed mouth gathers no feet"

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help with 817 and satpc32
by Tim Goodrich 30 Dec '08

30 Dec '08

Hi all, I just finally upgraded to general over the weekend, so I went out and got a Yeasu 817. However, I'm having problems with using it for Doppler tracking in SatPC32. Here's what it's doing. When I turn the control on, the radio will track the frequencies that are showing in SatPC32 for both the uplink and the downlink. It switches between the uplink and downlink frequencies quite often- about once per second. The radio will also switch to the correct mode (FM, etc). However, when I hit PTT, it transmits on the previously stored VFOb frequency. So, for example.... 1) I tune vfoa to 50.1Mhz, AM and vfob to 50.5Mhz, AM 2) I turn CAT control on from SatPC32 3) The radio starts switching between the vhf downlink frequency in USB and the uhf uplink frequency in USB about once per second to correct for Doppler 4) When I press transmit, it transmits at 50.1Mhz, but in LSB Obviously, it should be flipping between the VFOs (instead of 2 freq's in one VFO). So it seems like its flipping frequencies in one VFO and then trying to transmit in another VFO, where it changes the mode for transmit, but not the frequency that was originally stored. Any help please? Tim KC2DDS/AG

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LOTW and Logging Info
by Gary "Joe" Mayfield 30 Dec '08

30 Dec '08

If anyone is interested it is possible (fairly easy in hind sight) to make AC Log from N3FJP properly report OSCAR contacts in LOTW automatically. If you have worked me as kk0sd or ks5z via satellite those contacts should be in LOTW except for contacts made from my home of the last 2 years. They will go in next. After that I will go after my ka0yos logs. Speaking of older logs, has anyone entered QSOs from RS 10/11 in LOTW? My logs show it as RS 10/11, is there anyway now to determine if it was RS-10 or RS-11? Thanks and 73, Joe kk0sd

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ISS Repeater
by n1jez＠burlingtontelecom.net 30 Dec '08

30 Dec '08

Had a nice QSO with Clare, VE3NPC via the ISS repeater this morning during the 1235 pass over Vermont, FN34im. We were alone. I held the repeater longer today. Doppler tuning seems pretty critical. Clare was computer controlled. I was using manual tuning (OK, call me old school...) One of these days I'll hook up the radios for computer tuning. I got a copy of SatPC32 so maybe it's time. 73, Mike, N1JEZ AMSAT 29649 "A closed mouth gathers no feet"

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FT817 issues SATPC32
by Dr. Jay Garlitz 30 Dec '08

30 Dec '08

Tim, I have an FT817 as well and have had the same problem as described. I hope others can offer suggestions as I had the same experience in searching the online suggestions and none had it working properly. There were only a few settings to try to change and none were a solution for me. The difference here is that is an extra rig for me and not the one I usually use for satellites. Jay, AA4FL Message: 9 Date: Mon, 29 Dec 2008 19:51:29 -0800 From: "Tim Goodrich" <tim(a)timgoodrich.net> Subject: [amsat-bb] help with 817 and satpc32 To: <amsat-bb(a)amsat.org> Message-ID: <000001c96a31$e6ad0410$b4070c30$@net> Content-Type: text/plain; charset="us-ascii" Hi all, I just finally upgraded to general over the weekend, so I went out and got a Yeasu 817. However, I'm having problems with using it for Doppler tracking in SatPC32. Here's what it's doing. When I turn the control on, the radio will track the frequencies that are showing in SatPC32 for both the uplink and the downlink. It switches between the uplink and downlink frequencies quite often- about once per second. The radio will also switch to the correct mode (FM, etc). However, when I hit PTT, it transmits on the previously stored VFOb frequency. So, for example.... 1) I tune vfoa to 50.1Mhz, AM and vfob to 50.5Mhz, AM 2) I turn CAT control on from SatPC32 3) The radio starts switching between the vhf downlink frequency in USB and the uhf uplink frequency in USB about once per second to correct for Doppler 4) When I press transmit, it transmits at 50.1Mhz, but in LSB Obviously, it should be flipping between the VFOs (instead of 2 freq's in one VFO). So it seems like its flipping frequencies in one VFO and then trying to transmit in another VFO, where it changes the mode for transmit, but not the frequency that was originally stored. Any help please? Tim KC2DDS/AG

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Mesh Diosh and GS-5500
by D. Mynatt 30 Dec '08

30 Dec '08

I have been given a 7ft mesh dish from a local college but without a rotor or Az/El mechanism. I might be able to find a GS-5500 and was wondering what the group thought of using it as an Az/El system for the mesh. A commercial system would cost more than three times the price of a GS-5500. Any thoughts from the group? Dave // DM78qd // KA0SWT

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lindenblad observations
by francesco messineo 30 Dec '08

30 Dec '08

Good morning all, even if this setup probably won't be used by anyone I thought I'd share my findings. I've built a couple of lindenblads following the AA2TX articles. The EZ-lindenblad for 2m and the parasitic lindenblad for 70cm. This is for a 2 week temporary location in IS0 (JM49MG). Both antennas have been made with locally available hardware, not very far from original design anyway. The biggest difference is perhaps the parasitic elements for the 70 cm one which have a 4mm diameter instead of approximately the 3mm of original design. Both antennas are on the same pole, 1.5 meters apart and not very far from the roof (< 1m the 2m one), they have however a clear sky view. Cable runs are quite long, 20m of rg-213 on both bands and no preamps. Only RHCP versions made. Rig is ft-847 with internal preamps on. In 4 days I have tried almost all LEOs (but AO-16 and AO-27 which are non operational afaik). DO-64: never heard anything (is it operational?) AO-51: 435.300 output can be heard at times, some callsing can be undestood, never quieting the receiver. FM uplink in europe is too crowded to attempt any try at txing. 435.150 output is much lower than the 435.300 one, only rarely it can be heard but when it's heard I can hear myself briefly from the USB uplink. Obviously no contact is possible. SO-50: usually can't be heard, sometimes during a pass on positive QSBs the downlink can be heard very noisy and for a short time (so far only copied a full callsign). AO-07: downlink on mode B can be heard quite easily down to 3 degrees, uplink is next to impossible (50W out of the rig, CW only of course) but probably depends on the high level of power used in europe as during a pass over the atlantic and part of brazil I could hear my own signal down to 3 degrees and I couldn't hear any other signal. No contacts have been made, so far only heard my own signal a few times and very low (maybe the 432 MHz uplink is too far out of the optimal passband of the 435 MHz lindy?) FO-29: downlink can be heard, not very strong but workable, uplink is sometimes difficult but a lot easier than AO-07. No contacts made so far, have been calling CQ in CW for a few passes. VO-52: downlink easy to copy as on AO-07, quite easy to hear my own CW peaking at S3 during all passes over 5 degrees, no contacts made, heard only a lot of SSB stations, this is the easier sat with this setup. ISS: never heard any signal so far. I think I'll go back to the homemade V/U yagi "arrow" like on next travels, that's a real performer on LEOs. PS: the NB on FT-847 (first time using this rig) is quite uneffective, motors on the street still make an audible signal when passing by, it's attenuated but not like on all other rigs I know. Is there any fix for it? 73 Frank IS0/IZ8DWF

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I: I: ISS L / v Transponder 09.05 utc ITALY / Europe Pass
by Francesco Grappi 30 Dec '08

30 Dec '08

...sorry 08.05 utc Frank IW4DVZ -----Messaggio originale----- Da: amsat-bb-bounces(a)amsat.org [mailto:[email protected]] Per conto di Francesco Grappi Inviato: martedì 30 dicembre 2008 9.22 A: amsat-bb(a)amsat.org Oggetto: [amsat-bb] I: ISS L / v Transponder 09.05 utc ITALY / Europe Pass Priorità: Alta 09.05 utc ITALY /Europe Pass Hi All I tried ISS transponder L/V this morning..... TX FT 736R FM-Narrow + PA Output power 70 Watts 2x35 elements antennas linear pol. RX 2x11 elements cross yagi Also here nothing heard and unable to access L/V Transponder... Frank IW4DVZ -----Messaggio originale----- Da: amsat-bb-bounces(a)amsat.org [mailto:[email protected]] Per conto di David Barber Inviato: martedì 30 dicembre 2008 6.09 A: amsat-bb(a)amsat.org; sarex(a)amsat.org Cc: 'Frank H. Bauer' Oggetto: [amsat-bb] ISS L / v Repeater 04.49utc UK / Europe Pass 04.49utc UK / Europe pass. Nothing heard and unable to access L / v repeater. David G8OQW _______________________________________________ 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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