September 2013 - AMSAT-BB - mailman.amsat.org

Re: SO-50, IC-910H, and Sat PC32 Issues
by Andrew Glasbrenner 19 Sep '13

19 Sep '13

SO-50 uses a corner mounted single UHF whip for the downlink, so it is linearly polarized, and is often shielded by the body of the spacecraft. It also runs about 250mw, which is pretty low. By comparision FO-29 is circularly polarized. Operating portable on SO-50 it is extremely beneficial to be able to twist a yagi to match or peak polarity for best signal. A typical home station overcomes this with gain and circular polarity. As far as frequency, SO-50 has developed a shift in the downlink frequency that comes and goes. On a busy pass you can use the AFC function on the 910 to keep the downlink centered, or you can do as I have by setting up a series of entries in the doppler.sqf file moving the downlink frequency up and down in 2.5 khz steps. During a pass I will cycle through these to find the best one to match the frequency of the day. I hope these hints help... 73, Drew KO4MA -----Original Message----- >From: Les Rayburn <les(a)highnoonfilm.com> >Sent: Sep 19, 2013 1:23 PM >To: AMSAT Mailing List <amsat-bb(a)amsat.org>, starcom-bb(a)star-com.net >Subject: [amsat-bb] SO-50, IC-910H, and Sat PC32 Issues > >Before I ask again for assistance, I'd like to say that I've read the >"manual" for both the software and the rig, experimented, and tested on >my own trying to resolve these issues. This includes staying up well >past midnight so that I can run tests on the bird without bothering >other users too much. > >Here, briefly is a description of my station, and the issues I'm >experiencing. Any assistance or advice in resolving the problem would be >gratefully accepted: > >Running an Icom IC-910H into antennas in the attic. The 432 antenna is >an Arrow 7 element Yagi, mounted at a fixed elevation of 25 degrees. The >2 Meter antenna is a 6 element K1FO Yagi, mounted horizontal. Both can >be rotated on the stack in azimuth only. Feedline is 75' foot runs of >1/2" hardline with antennas mounted in the attic. > >The 432 antenna has an ARR mast mount pre-amp, while the 2 Meter antenna >has an SSB Electronics mast mount pre-amp. Performance on FO-29, VO-52 >is fair to good. High elevation passes on all satellites seem to give me >reception problems, but down nearer the horizon things are good. Hoping >to upgrade to AZ/EL in the near future. > >I've learned how to deal with Doppler on the other birds, and generally >can used the stored corrections in SATPC32, or adjust it on the fly >using the software to hear my own downlink well, and work other stations. > >SO-50 ISSUES >====================================================== >However, on FM I continue to struggle. > >A.) Reception is poor. Especially high elevation passes. >B.) Successful reception of other stations requires adjusting the RIT >control on the rig. Often to "plus" 5 KHz and sometimes to somewhere in >between 0 and +5 Khz. >C.) Switching the rig to FM Narrow mode helped, but did not resolve the >problem. >D.) Attempting to adjust for Doppler using the software control doesn't >seem to help much. >E.) I can only rarely hear my own downlink on this satellite, even in >the middle of the night when the bird is empty. >F.) Numerous reports of others calling me without success, even though >I'm getting into the bird fine. > >I realize that polarity is an issue with all satellites. Signals arrive >out of phase, and I have no way to compensate. Also having a fixed >elevation is a problem, and explains the poor performance at high >elevation. But I fail to understand why the system seems to work well on >other birds, but not SO-50. What am I missing? > > > >-- >-- >73, > >Les Rayburn, N1LF >121 Mayfair Park >Maylene, AL 35114 >EM63nf > >6M VUCC #1712 >AMSAT #38965 >Grid Bandits #222 >Southeastern VHF Society >Central States VHF Society Life Member >Six Club #2484 > >Active on 6 Meters thru 1296, 10GHz & Light > >_______________________________________________ >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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Northern Europe AO-7
by Bob- W7LRD 19 Sep '13

19 Sep '13

Hello those in N. Eu. at 1817z I will be looking for you 145.950+/- 73 Bob W7LRD CN87

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SO-50, IC-910H, and Sat PC32 Issues
by Les Rayburn 19 Sep '13

19 Sep '13

Before I ask again for assistance, I'd like to say that I've read the "manual" for both the software and the rig, experimented, and tested on my own trying to resolve these issues. This includes staying up well past midnight so that I can run tests on the bird without bothering other users too much. Here, briefly is a description of my station, and the issues I'm experiencing. Any assistance or advice in resolving the problem would be gratefully accepted: Running an Icom IC-910H into antennas in the attic. The 432 antenna is an Arrow 7 element Yagi, mounted at a fixed elevation of 25 degrees. The 2 Meter antenna is a 6 element K1FO Yagi, mounted horizontal. Both can be rotated on the stack in azimuth only. Feedline is 75' foot runs of 1/2" hardline with antennas mounted in the attic. The 432 antenna has an ARR mast mount pre-amp, while the 2 Meter antenna has an SSB Electronics mast mount pre-amp. Performance on FO-29, VO-52 is fair to good. High elevation passes on all satellites seem to give me reception problems, but down nearer the horizon things are good. Hoping to upgrade to AZ/EL in the near future. I've learned how to deal with Doppler on the other birds, and generally can used the stored corrections in SATPC32, or adjust it on the fly using the software to hear my own downlink well, and work other stations. SO-50 ISSUES ====================================================== However, on FM I continue to struggle. A.) Reception is poor. Especially high elevation passes. B.) Successful reception of other stations requires adjusting the RIT control on the rig. Often to "plus" 5 KHz and sometimes to somewhere in between 0 and +5 Khz. C.) Switching the rig to FM Narrow mode helped, but did not resolve the problem. D.) Attempting to adjust for Doppler using the software control doesn't seem to help much. E.) I can only rarely hear my own downlink on this satellite, even in the middle of the night when the bird is empty. F.) Numerous reports of others calling me without success, even though I'm getting into the bird fine. I realize that polarity is an issue with all satellites. Signals arrive out of phase, and I have no way to compensate. Also having a fixed elevation is a problem, and explains the poor performance at high elevation. But I fail to understand why the system seems to work well on other birds, but not SO-50. What am I missing? -- -- 73, Les Rayburn, N1LF 121 Mayfair Park Maylene, AL 35114 EM63nf 6M VUCC #1712 AMSAT #38965 Grid Bandits #222 Southeastern VHF Society Central States VHF Society Life Member Six Club #2484 Active on 6 Meters thru 1296, 10GHz & Light

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Re: So Long
by Daniel Schultz 19 Sep '13

19 Sep '13

> Is it possible to carry P3E? numerous test launch use dummy mass why not > launching one bigger satellite instead of a bunch of small one? The Cygnus launch only goes to LEO, I thought you wanted a higher orbit for P3E. The Cubesats that were deployed on the test launch only stayed up for a week before reentering. Also, integrating a large and complex satellite with a propulsion system is probably adding too many complications to a program that is under immense pressure not to screw up the first launch. Inert aluminum proof mass cylinders are much easier to integrate into the launch vehicle. > Getting up to $250,000 on Kickstarter may just about be feasible, enough for a 3U CubeSat > in a low 700 km orbit, but I'd suggest larger amounts are out of the question. You don't need Kickstarter, just call Martha or donate online. AMSAT was doing crowd sourcing decades before it became cool. Also, would you guys PLEASE LEARN TO TRIM YOUR EMAIL when you hit "reply", there is no need to quote and rebroadcast the entire days amsat-bb digest when you want to reply to a message. Dan Schultz N8FGV

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HEO lottery
by Bob- W7LRD 18 Sep '13

18 Sep '13

I never buy lottery tickets. However today at the grocery store I saw the powerball up to $400M. I bought a couple thinking HEO. 73 Bob W7LRD

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Last Call for Papers for 2013 Symposium
by Daniel Schultz 18 Sep '13

18 Sep '13

This is the final call for papers for the 2013 AMSAT Annual Meeting and Space Symposium to be held on the weekend of November 1 - 3, 2013, at the Marriott Hobby Airport Hotel, Houston, Texas. Proposals for papers, symposium presentations and poster presentations are invited on any topic of interest to the amateur satellite community. We request a tentative title of your presentation as soon as possible, with final copy to be submitted by October 5 for inclusion in the printed proceedings. Abstracts and papers should be sent to Dan Schultz at n8fgv(a)amsat.org Dan Schultz, N8FGV

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Update On Cygnus
by B J 18 Sep '13

18 Sep '13

http://www.parabolicarc.com/2013/09/18/50040/ Lots of pictures at: http://www.flickr.com/photos/orbitalsciences/ 73s Bernhard VA6BMJ @ DO33FL

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NEED help with a 2M receive preamp for ARISS contact ....
by Rob 18 Sep '13

18 Sep '13

Hello amsat-bbers .... I'm looking for a 2M GaAsFET preamp for an upcoming ARISS contact in Warren County, NJ .... Needs to be RF switchable and be able to withstand 100W of transmit power .... something like this: http://goo.gl/0m3VKO Would be interested in: LOAN, LEASE, PURCHASE ... or other creative arrangement ..... If you have any thoughts please email me direct .... Thanks, --> Rob, KA2PBT

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Thought experiment ... Rockets and balloons
by Rob 18 Sep '13

18 Sep '13

I'm not a rocket scientist but I have an active imagination ..... Thinking of a recent XKCD .... to achieve orbit .... the hard part isn't the altitude it's the velocity .... Would there be any advantage (cost effective) carrying a launch vehicle say to 37KM ... think Red Bull Stratos .... and firing the engines there??? So you're already 37KM up .... there's a lot less atmospheric drag .... This would be like a drop from a plane ... but even higher .... Thoughts??? de KA2PBT

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Re: The "Good Ole Days" are now
by george abbott 18 Sep '13

18 Sep '13

Thanks' for sharing your experiences. I'm inspired! W1GMA > Date: Wed, 18 Sep 2013 15:31:54 -0500 > From: les(a)highnoonfilm.com > To: amsat-bb(a)amsat.org > Subject: [amsat-bb] The "Good Ole Days" are now > > Like many hams (I suspect), I dreamed of working satellites for decades. > Followed them with at least a passing interest but always seemed to put > them off till "someday". Even during the craze of the "work satellites > with your handheld", I was distracted by other priorities. When I got > involved in VHF/UHF a few years ago, and purchased an Icom IC-910H, I > kept thinking I'd finally pull the trigger. But years passed without > anything other than weak-signal contacts being made on that rig. > > A few months ago, I finally decided to give it a try. Downloaded > SATPC32, and updated my keps. FO-29 was the next satellite coming my > way, so when I was inside the footprint, I tuned around a bit, and found > some stations coming in. Cool! I was actually hearing hams on > satellite---next up was answering a CQ...nervously I pushed the PTT on > the mic. > > 82 grids and a few hundred contacts later, I'm having a ball! > > I don't miss the birds that came before, but just enjoy what we have > now. My only complaint might be that more folks are not active on F0-29 > and VO-52. Even SO-50 can be nearly empty after midnight. > > My understanding is that within the next year we'll have 2 or 3 more > linear LEO satellites, and possibly another FM bird, right? While we may > not work a lot of DX on those, we should get to the point where no one > has to wait long for "something" to be overhead. That's exciting to me! > > AMSAT is staffed with wonderful volunteers, and seems to be doing great > work. I'm thrilled to be a member, even if it is #38965. > > The good ole days are now. Get on the birds and make some contacts. I > need your grid! (ha, ha) > > > -- > -- > 73, > > Les Rayburn, N1LF > 121 Mayfair Park > Maylene, AL 35114 > EM63nf > > 6M VUCC #1712 > AMSAT #38965 > Grid Bandits #222 > Southeastern VHF Society > Central States VHF Society Life Member > Six Club #2484 > > Active on 6 Meters thru 1296, 10GHz & Light > > _______________________________________________ > 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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