April 2017 - AMSAT-BB - mailman.amsat.org

Re: [amsat-bb] Linear vs Circular Polarization
by Brady Gordon 13 Apr '17

13 Apr '17

Thanks everyone for the replies! It is very helpful, and I do appreciate it. The SV1BSX site is great, and the visualizations really helped me understand how circular polarization works. Thanks especially Zach for letting me know about M2 Antennas using the relay at the feedpoint. That's also a good point about having to cut impedance transformation lines, even if I did use a physical 1/4 wave offset. I may build something to switch between both linear and circular polarizations. I'm hoping to build the antennas in time for Field Day, so I can do a satellite demo for my club. Thanks again, and I hope to be able to work you on the sats soon! 73, Brady AC0XR

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W5PFG/P FM02 South Carolina
by Clayton Coleman 13 Apr '17

13 Apr '17

I will be operating satellites from the Charleston, South Carolina area in gridsquare FM02 between April 23-28. During my FM02 stay, I plan to activate nearby FM03, EM92, and EM93 grids. Follow me on Twitter for pass updates: @w5pfg http://www.twitter.com/w5pfg I am available to make limited schedules with European and South American stations interested in confirming the grid FM02. Contact me via direct reply to this email. 73 Clayton W5PFG

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funcube dongle
by willmarbrowns＠charter.net 13 Apr '17

13 Apr '17

looking to buy a funcube pro+...any one willing to part with?bruce ke0lx

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Orbitron Question
by Paul Ecker 13 Apr '17

13 Apr '17

I read about Orbitron on this list, never have used but just downloaded. Is there a way to have it just list the amateur satellites? Paul kc2nyu

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Re: [amsat-bb] Linear vs Circular Polarization
by Richard Tejera 12 Apr '17

12 Apr '17

Brady, Domenici, I8cvs SK had published a pair of articles on making a switching relay between vertical, Horizontal, LHCP & RHCP. he sent me PDF's, which are in my to do someday folder. Contact me off list (email is good on QRZ), and I will send them to you. They are for 70cm, but certainly can be adapted for 2m easily enough. Rick Tejera K7TEJ Saguaro Astronomy Club www.SaguaroAstro.org Thunderbird Amateur Radio Club www.w7tbc.org On April 12, 2017, at 14:11, Brady Gordon <ac0xr(a)lowswr.com> wrote: Hi Everyone, I'm working on building a pair of crossed yagis for 2m and 70cm, and I have some questions. I apologize if this has been discussed before, but I couldn't find answers online so I was hoping you all could help me out. First, it seems easiest to me to build an antenna system that can either switch between vertical and horizontal linear polarizations, or between right hand and left hand circular polarization. Which would be more useful? And is it worth the extra effort to build an antenna system that can switch between all four polarizations? Also, I've been looking at the different ways of achieving circular polarization. I like the idea of using mechanical 1/4 wave separation between the two yagis so I don't have to cut phasing lines. Would it be possible to switch polarizations by putting a relay at the feedpoint of one of the yagis and switching which side of the driven element the center conductor and shield of the coax goes to? I've never seen this done before, but it seems to me it would work. Any thoughts? Thanks and 73, Brady AC0XR _______________________________________________ Sent via AMSAT-BB(a)amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb

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Linear vs Circular Polarization
by Brady Gordon 12 Apr '17

12 Apr '17

Hi Everyone, I'm working on building a pair of crossed yagis for 2m and 70cm, and I have some questions. I apologize if this has been discussed before, but I couldn't find answers online so I was hoping you all could help me out. First, it seems easiest to me to build an antenna system that can either switch between vertical and horizontal linear polarizations, or between right hand and left hand circular polarization. Which would be more useful? And is it worth the extra effort to build an antenna system that can switch between all four polarizations? Also, I've been looking at the different ways of achieving circular polarization. I like the idea of using mechanical 1/4 wave separation between the two yagis so I don't have to cut phasing lines. Would it be possible to switch polarizations by putting a relay at the feedpoint of one of the yagis and switching which side of the driven element the center conductor and shield of the coax goes to? I've never seen this done before, but it seems to me it would work. Any thoughts? Thanks and 73, Brady AC0XR

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Vhf sat ants for sale
by jeffory broughton 12 Apr '17

12 Apr '17

One has the phasing Harness for rhcp, The other does not,is is set up for two feedlines,one for horiz,one for vert. Both Cushcraft A144-20T.ONE LIKE BRAND NEW $100 ,ONE NOT SO NEW $80 .BOTH PLUS SHIPPING. jeff broughton

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Yaesu FT-847 forsale
by n4qwf . 12 Apr '17

12 Apr '17

I am selling my FT-847 satellite radio. I offer it here before it goes to Raleigh Hamfest this weekend. I am asking $895.00 plus shipping. It has the power cable and hand mic and original manual. It ships in the original box. It is in excellent condition from a non-smoking home. First response gets it. Thanks and 73<<John -- N4QWF Amateur Radio Operator Email N4QWF(a)AMSAT.ORG Formerly KC4AHW VK3FEZ 8BDXCC DXCC mixed 327 WAS HF #57,114 WAS Triple Play #1270 WAZ HF #9073 AAA All Africa Award #1734 VUCC SAT #135 WAS SAT #296 OSCAR-11 20th birthday #1 51 on AO-51 #13 LON -79.256 LAT 37.459 Grid FM07il >From the Foothills of the Blue Ridge Mountains *Life should not be a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming - "WOW, What a ride!"

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Re: [amsat-bb] Upcoming ARISS Contact Schedule as of 2017-04-11 05:00 UTC
by charles sikes 12 Apr '17

12 Apr '17

You might try contacting Darryl Paule KI6MSP. I believe he is coordinating the event for Brookhaven. Darryl's email is ki6msp(a)gmail.com Charlie, KZ6T

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KB1RVT on the sats
by Daniel "Nick" Kucij 12 Apr '17

12 Apr '17

Fellow satellite ops, I have moved and left my shack location, where I operated since I got my license in 2009. The move is due to down-sizing, necessitated by aging. As some may know, I operated from a second floor room in the northeast corner of our Vermont home, using an Arrow antenna indoors. It worked remarkably well, especially on the linear transponders in directions from north to south. West was a challenge due to the building, but Europe was a sweet spot. It was a great run, I now have over 1500 grids confirmed. Thanks to everyone on the birds, especially the rovers! Unfortunately, my new location in a condo, appears to be not so conducive for working the birds. I may try some occasional outdoor ops from portable locations this summer, but will miss the regular comradery of our small fraternity, it has been a lot of fun! Enjoy the hobby and be good to each other! 73 and gud DX! Nick, KB1RVT Sent from my iPad

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