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

ISS
by Howard Kowall 25 Jul '09

25 Jul '09

Hello to all Is the ISS operational I haven herd anything on In a long time Been listening to 145.800 not even a peep thanks to all who respond Howard VE4ISP

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Cross boom question
by Kevin Groth 25 Jul '09

25 Jul '09

I have just finished building a set of 2m and 440mhz circular polarized beams to work the birds. (tired of standing in the heat and cold outside!) I tried to save a little bit of money by building a wood dowel inserted into a sched 40 uv resistant pipe. I hung the beams on either side of the cross boom and it sags way too much and is ugly. I thought about using some eyebolts and some nylon cording for support to the vertical mast, but I'm trying to keep everything as clean as possible for the neighbors. I would really rather not have to purchase a fiberglass satellite boom commercially, but if I have to, I will. I have a bunch of 1.75" aluminum pipe that would be more than able to support most anything I plan to add to the antenna collection in the future (1.2 and 2.4 ghz). My question is how much of a difference would it make if I mounted the 2m and 440 beams in an X position to the aluminum beam? I have read some short answers that it would minimize the swr issue, but haven't really found an answer that I am comfortable with. Also, how would that effect a later addition like a 1.2 or 2.4 ghz antenna.? My current antennas are a KLM 2m-14c and a 435-40cx, both circular polarized and switchable RH and LH polarization. Does anyone have any experience with a metal crossboom? Thanks! Kevin N9EME Fort Worth, TX

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Elk Ant/ metal mast??
by Jerry Felts 25 Jul '09

25 Jul '09

I think I'm going to get a used Elk ant to mount on top of my 20ft tower or at least would like to. It would go on the top of the lil 20ft tower and 5 ft above it would be a 9 el 2m yagi. The mast is metal and I'm wondering how to mount it to the mast and mostly will the metal mast work ok??? -- Jerry - NR5A - South Dakota http://nr5abikeblog.blogspot.com/ http://nr5abeaconblog.blogspot.com/

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Re: Cross boom question
by Jim Jerzycke 25 Jul '09

25 Jul '09

This has been gone over a zillion times. Short answer; Mount them in an "X" configuration and don't worry about it. http://www.g6lvb.com/fibermetalboom.htm --- On Sat, 7/25/09, Kevin Groth <hislens(a)gmail.com> wrote: From: Kevin Groth <hislens(a)gmail.com> Subject: [amsat-bb] Cross boom question To: amsat-bb(a)amsat.org Date: Saturday, July 25, 2009, 1:47 PM I have just finished building a set of 2m and 440mhz circular polarized beams to work the birds. (tired of standing in the heat and cold outside!) I tried to save a little bit of money by building a wood dowel inserted into a sched 40 uv resistant pipe. I hung the beams on either side of the cross boom and it sags way too much and is ugly. I thought about using some eyebolts and some nylon cording for support to the vertical mast, but I'm trying to keep everything as clean as possible for the neighbors. I would really rather not have to purchase a fiberglass satellite boom commercially, but if I have to, I will. I have a bunch of 1.75" aluminum pipe that would be more than able to support most anything I plan to add to the antenna collection in the future (1.2 and 2.4 ghz). My question is how much of a difference would it make if I mounted the 2m and 440 beams in an X position to the aluminum beam? I have read some short answers that it would minimize the swr issue, but haven't really found an answer that I am comfortable with. Also, how would that effect a later addition like a 1.2 or 2.4 ghz antenna.? My current antennas are a KLM 2m-14c and a 435-40cx, both circular polarized and switchable RH and LH polarization. Does anyone have any experience with a metal crossboom? Thanks! Kevin N9EME Fort Worth, TX _______________________________________________ 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: Hamsat article on the Make blog
by Bruce Robertson 25 Jul '09

25 Jul '09

If you haven't taken a look at this introductory article, you really should. It does so many things well, in my opinion. First, it doesn't assume the reader is (yet!) a ham. Second, it uses very simple tools, like heavens-above.com, to ensure success. Finally, it has that makergeek cred from the homebrew antenna setup. It would have been a great intro for me when I was starting up. 73, Bruce VE9QRP On Thu, Jul 23, 2009 at 4:09 PM, Ollie Eisman<ollie(a)ollietech.com> wrote: > FYI > > http://blog.makezine.com/archive/2009/07/catching_satellites_on_ham_radio.h…

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Left /Right Hand polarization ...
by John Papay 25 Jul '09

25 Jul '09

Myles, AO51 435.300 is right hand circular polarization (RHCP). AO51 435.150 is left hand (LHCP). If you try to hear a LHCP signal with a RHCP antenna that is really right hand, you will have a drop in signal that can exceed 20db. This will make the downlink unreadable at low elevations. You definitely want to have switchable polarization on UHF if at all possible. The reason that people have a hard time hearing SO50 when they are using RHCP is that although the antennas are supposed to be linear polarized, they don't fare well on RHCP throughout the pass. I find that I have to switch several times between right and left in order to hear the bird throughout the pass. Before I had switching, it was hit and miss with that bird. The two meter side is not as important to switch unless you plan to operate AO7 and VO52 which have downlinks on 2 meters. If you do operate those birds, you'll be able to do much better if you can switch. Switching the uplink on UHF on those birds sometimes makes a big difference too. If you are serious about operating the birds, the investment in polarity switching will be well worth it. John K8YSE

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FX614
by Andy Brian 25 Jul '09

25 Jul '09

HI, I'm looking for any simple source code in C-language for FX-614 (ax.25 decoder) for undestanding simple ax.25 protocol. I found only few asm code for PIC16, but c-lanugage is easily to adopt to other microcontrollers. I tried to connect FX614 IC like in HITSAT http://www.hit.ac.jp/~satori/hitsat/img/decord.bmp and read at RX PC port with rs232 terminal programme, but I didn't receive any useful frame with b011111110 start (like describet in ). After this I found that all modem using pin CTS on RS232 port, I don't know how to handle this with PC to read directy with rs232 RXD port like HEX or binary values to see raw values of packet frames? It is possible to read values from FX614 (through max232 ) with PC to see raw format? So I'm looking for any simple source code in C to find how to decode signal from fx614 to microcontrollers port and then to PC Thanks for your help all the best Andy

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PocketSat+ on Nokia N810
by Greg D. 25 Jul '09

25 Jul '09

Hi folks, I recently treated myself to a new toy - the Nokia N810 "Internet Tablet". (Think iPod Touch with a higher resolution screen, real GPS, real keyboard, and it runs Linux so the apps multi-task, and are free.) Thought I'd pass this on... One of the challenges I faced in this consolidation was finding equivalent apps to the ones I was using on multiple other platforms, including some sort of satellite tracking program. I figured I could at least port Predict over, given the Linux software base. Then I found the Garnet VM program, which is a Palm virtual machine. Loaded it up and installed PocketSat+, and it works really well. In fact, it's faster on the Nokia N810 than it was on my Palm Vx. Just be sure to get all the various clock settings right, between the N810, virtual machine, and the application right, so you don't apply daylight savings twice. Enjoy, Greg KO6TH _________________________________________________________________ Windows Live™ SkyDrive™: Store, access, and share your photos. See how. http://windowslive.com/Online/SkyDrive?ocid=TXT_TAGLM_WL_CS_SD_photos_072009

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Elk Antenna Mounted on a Camera Tripod
by Vince Staffo 24 Jul '09

24 Jul '09

Has anyone used the Elk 2M/440 Log Periodic Beam Antenna mounted on a Camera Tripod? I would appreciate your experience/technique in mounting it. Thank You, Vince, WB2FYZ

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Re: Rare Grids and Gridpeditions
by John Papay 24 Jul '09

24 Jul '09

Drew, I appreciate your comments about what AO-51 can and cannot do. There is no problem if the v/u mode comes down on 435.150 rather than 435.300 except for the polarization difference. Those with Right Hand Circular Polarization (RHCP) will have a difficult time hearing the Left hand (LHCP) downlink. Those with yagi's etc won't be affected and that includes most of the new people. A downlink on 435.150 is better than no UHF Voice downlink at all. As far as dxpeditioners working ssb birds, most of us can do that. But who are we going to work? - only the few that have ssb equipment. The new people starting out are likely to only have a FM handheld or mobile. These are the people that will be going for their first award. As they progress, they'll start working towards their first 100 grid VUCC award and maybe Worked All States, especially if they are on the west coast and can work Hawaii on a FM bird. We cannot expect everyone to invest in L and S band equipment to work the handful of people who operate those modes. If it weren't for the people that bought their radios/antennas/converters a long time ago, even fewer would be operating L/S. It's a lot harder to work grids now than it was years back. If you worked your 550 grids on birds that have the footprint of AO-51, you're a stellar operator. These days you have to pull out the stops to do it and if it weren't for the grid dxpeditioners, it would be tough to do half that amount. Without V/U FM, you don't get to those totals very fast, if ever, on today's birds. There does need to be a balance between modes and AO-51 is certainly a versatile satellite that can serve many different interests. What we need to keep in mind is that new people are the future of AMSAT. If they don't have an FM voice mode, there is no other likely entry point for them. And if no one is going out on grid dxpeditions because there is so little v/u airtime per day, the organization will never grow. There would be no interest in DXCC if there were no dxpeditions. I think that there would be a lot less interest in operating satellites if there was no VUCC and grid dxpeditions to facilitate working something new on a regular basis. Making a contact with the same people over and over gets old quickly. Put someone like WD9EWK in Utah, ND9M all over the eastern US including Delaware, KD8CAO in northeastern Michigan and Drummond Island, KB0RZD on a 4 corner grid boundary in Missouri and even K8YSE in Delaware for those that missed ND9M, and AO-51 COMES ALIVE. XE2AT who is at the top of the VUCC leader board with over 900 grids worked is in there calling KD8CAO in EN86 and EN76. There are no pileups on L/S and the BBS. That being said, I only ask that configurations that preclude a FM V/U transponder be kept to a minimum. We need to do everything we can to encourage new people to enter the world of satellites and we need to support those who operate from other grids and give everyone something to work for. I will be listening for you on AO-7 et. al. Have a great trip. Don't forget to post your operating schedule on the amsat-bb so we know when to look for you and what grids you'll be in. John K8YSE Date: Thu, 23 Jul 2009 16:43:03 -0400 From: "Andrew Glasbrenner" <glasbrenner(a)mindspring.com> Subject: [amsat-bb] Re: Rare Grids and Gridpeditions To: <amsat-bb(a)amsat.org>, "John Papay" <john(a)papays.com> Message-ID: <58370780F3A14122A8BB648728DFAD90@Andrewlaptop> Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original John, I certainly understand where you are coming from, although I disagree with some of your positions. AO-51 is currently our only satellite with multiple modes (other than ISS), our only S band satellite, our only BBS, our only L band satellite, etc. Unfortunately our power budget doesn't allow us to run every mode we want to at the same time. This problem will only get worse as the batteries age. We are already at the point where after this extended period of mostly full illumination, we will most likely only be able to run one transmitter at any time, and possibly not the S band in eclipse at -all-. The good news is that the full illumination lasts for quite a while, and during this period we can support two UHF transmitters at a high power level, or one UHF at modest power and the S band transmitter. If we run separate S and UHF, the UHF downlink will have to be on 435.150, as the 435.300 and S transmitters share an audio path. So...that being said, do not expect us to completely forego L and S just for more grid swapping, as fun as it is (I'm at 550 confirmed). Send your requests in early for whatever mode you'd like, and we will try to honor them. Meanwhile, get your S band downconverters ready for portable ops, your 817s and 706s working with SatPC32 on a laptop, and be ready to occasionally run your grid trips on ALL the satellites. It's a real shame to hear so many ops on V/U FM, and so few on V/U and U/V SSB/CW. Since I try to walk the walk, look for me on the SSB -and- FM birds as G/ and OZ/KO4MA over the next 2.5 weeks. I hope to stretch the footprint to North America on FO-29 and AO-7 with my little 817 and Arrow setup. Mode requests should go to ao51-modes(a)amsat.org, not to me direct. 73, Drew KO4MA > We have enjoyed a long stretch of AO51 being in the V/U mode on > 435.300. After the end of the month, the bird will be in sunlight > continuously and that will allow higher power and other modes to be > used. If AO51 is in a non-V/U voice mode, as it was for a 2 week period > not long ago, grid dxpeditions are not going to be worthwhile. If > you plan a vacation ahead of time, you might find later that the bird > will not be in a v/u voice mode during your trip. > > The Operations Team sets the schedule and they do it based upon > requests from the membership for alternate modes. Personally I think > that there should always be a 435.300/145.92 mode available. Everyone > who is interested in chasing grids or activating grids away from their > home > should email KO4MA and request that V/U voice remain on. You cannot > plan anything if you don't know if AO51 will be in V/U voice during your > trip. The schedule is based upon input from the membership and if we > don't make our requests, those that want the bird in other modes (both > transponders) will most likely be served. The second transponder is fine > for other modes but there are probably some modes that cannot be activated > if V/U voice is to remain on. Maybe Drew can clarify this for us. > > There are some that would say that there are other satellites that can > be used for FM voice. Very true, however, if you are out there trying > to activate grids, not having AO51 available is a handicap. You spend a > lot of money to do it and then have 1/3 of your potential air time, on the > best FM satellite up there, not available to you. It makes no sense. > > I'm on L band now and will have S band RX running soon. I enjoy setting > up for different modes. But after you work a few stations in those modes, > and fine tune your equipment, there's not much left. Chasing grids never > ends. There's always one more to work. > > If you are interested in working or activating new grids, please email > KO4MA > and request that AO51 always have one V/U voice transponder available. > There > is no guarantee that this will always work, but if there are no emails, it > is > likely that there will be more periods of non V/U voice on AO51. > > John K8YSE John Papay john(a)papays.com

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