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

Satellite Operations from Guernsey
by Peter Goodhall 22 Jul '13

22 Jul '13

Hi All, Just a quick note to say that from the 24th of July till the 30th of July, I will be active sporadically on satellite passes from Guernsey (IN89RL) as 2U0SQL. I shall be focusing on FO-29 and SO-50 passes but no firm pass times, but hopefully will have internet access and will try posting on Twitter (@2E0SQL) when I'll be on. Due to this being camping I will be battery powered using a FT-817 and a Arrow antenna. If anyone needs a QSL Card its direct to 2E0SQL or bureau. 73, -- Peter Goodhall, 2E0SQL/2U0SQL

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Fw: Delivery Status Notification for Ing. Pavel Milanes Costa <[email protected]>
by i8cvs 22 Jul '13

22 Jul '13

Hi Pavel, CO7WT My article is a pdf file about 3 MB long and it was rejected bak to me by your system. Sorry ! 73" de i8CVS Domenico ----- Original Message ----- From: "Mail Delivery Service" <postmaster(a)tin.it> To: <domenico.i8cvs(a)tin.it> Sent: Monday, July 22, 2013 11:37 AM Subject: Delivery Status Notification > - These recipients of your message have been processed by the mail server: > co7wt(a)frcuba.co.cu; Failed; 5.3.4 (message too big for system) > > Remote MTA mail.frcuba.co.cu: network error > > > - SMTP protocol diagnostic: 552 Message size exceeds maximum permitted > > ---------------------------------------------------------------------------- ---- > Return-Path: <domenico.i8cvs(a)tin.it> > Received: from i8cvs (87.4.173.180) by vsmtp4.tin.it (8.6.060.26) > id 51DD1E01017CCA8B; Mon, 22 Jul 2013 11:36:56 +0200 > Message-ID: <002701ce86be$be606660$0401a8c0@i8cvs> > From: "i8cvs" <domenico.i8cvs(a)tin.it> > To: "pe0sat" <pe0sat(a)vgnet.nl>, > "Jeff Moore" <tnetcenter(a)gmail.com>, > <wb4gcs(a)wb4gcs.org>, > <Ab4ab(a)aol.com>, > <co7wt(a)frcuba.co.cu> > Subject: [amsat-bb] 1/2 Wave "cavity" filter design? > Date: Mon, 22 Jul 2013 11:34:58 +0200 > MIME-Version: 1.0 > Content-Type: multipart/mixed; > boundary="----=_NextPart_000_0022_01CE86CF.7EA0E930" > X-Priority: 3 > X-MSMail-Priority: Normal > X-Mailer: Microsoft Outlook Express 6.00.2800.2001 > X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.2001 > >

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Re: Gospodin Murphy was right!
by Armando Mercado 22 Jul '13

22 Jul '13

Hello, Sounds familiar. The Genesis Sample Return Probe crash landed in Utah in 2001 when its parachute failed to deploy. Root cause was an accelerometer that was installed backwards. 73 Armando N8IGJ

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Slime Mold CubeSat gets into the media
by M5AKA 22 Jul '13

22 Jul '13

A brief mention of the Slime Mold CubeSat posted last March on the AMSAT-UK and Southgatearc.org sites has been picked up by one of the Space.Com website writers, Leonard David, who has written a good article which retained a mention of amateur radio. It's Summer in the northern hemisphereand media outlets can be short of stories at this time of year so Leonards story has in turn been picked up by a few other news outlets and hopefully that will spread. I guess the thought of Slime in Space captures the imagination.Most of the resulting stories seem to have retained the mention of amateur radio. You can read Leonard David's article at http://www.space.com/21982-space-slime-grows-mold-tiny-satellite.html March AUK mention http://amsat-uk.org/2013/03/15/teikyosat-3-slime-mold-from-space/ 73 Trevor M5AKA ----

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Gospodin Murphy was right!
by Alan 21 Jul '13

21 Jul '13

An interesting article on the recent launch failure of a Proton-M: http://preview.tinyurl.com/kt5x9hw The latest in a long line of bizarre, expensive errors in the world launch business. 73s, Alan WA4SCA

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1/2 Wave "cavity" filter design?
by Robert Bruninga 21 Jul '13

21 Jul '13

Given the classic 1/2 wave cavity filter, what is the relationship between inner cavity and center conductor sizes? Of course bigger is better, but what is "OK". This is a 1/2 wavelength tube with a center conductor shorted at each end. The input is loop coupled at one end, an output is loop coupled at the other end. In the middle is a tiny variable capacitor (usually just a screw) to tune to resonance. In the limit, as the cavity size shrinks, you can end up with what could be considered as just a piece of 1/2wave coax. Im looking for a really cheap Home-Depot plumbing design that 15 people can reproduce to give them good front end antenna filtering when operating on mountain tops adjacent to other RF souces. (say within 100 yards, not permanent installations which of course should spare no expense at getting the best cavities possible). We just finished our 4th annual Golden Packet attempt from Maine to Georgia along the Appalachian trail and many stations were plagued with front end overload. http://aprs.org/at-golden-packet.html I'd like to come up with a 3/4" copper pipe design that is robust, provides sevral dB of out of band rejection. Im trying to understand the parameters that drive the size of the center conductor. Normally bigger is better for better bandwidth, but I think smaller will give me steeper skirts and better rejection? I dont mind say 2 or more dB insertion loss, because as it is, front end-overload is making us totally deaf and anything would be bettter. Lastly, I think such a 1/2wave filter will also pass as a 1.5wave pass filter on UHF. We need dual band, since we use dual band rigs and coordinate on UHF voice from the same antennas and coax used for the VHF packet.

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Fwd: AMSAT-UK Colloquium Videos Now Available Online
by Mark Thompson 21 Jul '13

21 Jul '13

----- Forwarded Message ----- From: MI5AKA <m5aka(a)yahoo.co.uk> To: Digital ATV Group <DigitalATV(a)yahoogroups.com> Sent: Saturday, July 20, 2013 5:50 PM Subject: [DigitalATV] AMSAT-UK Colloquium Videos Now Available Online Thanks to the hard work of volunteers from the British Amateur Television Club (BATC) videos of the presentations given to the AMSAT-UK International Space Colloquium held in Guildford, July 20-21, 2013 are now available to download or watch online.The ISS DATV presentation is at the end of the Columbus Lifecycles video.See http://amsat-uk.org/2013/07/20/amsat-uk-colloquium-videos-now-available/Live Webcast of International Space Colloquium continues Sunday, July 21 http://amsat-uk.org/2013/07/18/webcast-of-international-space-colloquium/ The Colloquium schedule (times in BST, GMT+1) can be seen athttp://tinyurl.com/2013ColloquiumSchedule ----73 Trevor M5AKAAMSAT-UK website http://amsat-uk.org/Facebook https://www.facebook.com/pages/AMSAT-UK/208113275898396Twitter https://twitter.com/AMSAT_UK---- __._,_.___ Reply via web post Reply to sender Reply to group Start a New Topic Messages in this topic (1) Recent Activity: * New Members 2 * New Files 1 Visit Your Group Switch to: Text-Only, Daily Digest • Unsubscribe • Terms of Use • Send us Feedback . __,_._,___

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AMSAT-UK Colloquium Videos Now Available Online
by M5AKA 20 Jul '13

20 Jul '13

Thanks to the hard work of volunteers from the British Amateur Television Club (BATC) videos of the presentations given to the AMSAT-UK International Space Colloquium held in Guildford, July 20-21, 2013 are now available online. See http://amsat-uk.org/2013/07/20/amsat-uk-colloquium-videos-now-available/ Live Webcast of International Space Colloquium continues Sunday, July 21 http://amsat-uk.org/2013/07/18/webcast-of-international-space-colloquium/ The Colloquium schedule (times in BST, GMT+1) can be seen at http://tinyurl.com/2013ColloquiumSchedule ---- 73 Trevor M5AKA AMSAT-UK website http://amsat-uk.org/ Facebook https://www.facebook.com/pages/AMSAT-UK/208113275898396 Twitter https://twitter.com/AMSAT_UK ----

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AO-7 mode B
by Roland Zurmely 20 Jul '13

20 Jul '13

Very week signal !... on orbit #177000 over Brazil, at 20:20 UTC. Problem with solar panels ? or illumination ? QSO with PU2RAS. 73 de Roland PY4ZBZ

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QB50: Amateur Radio transponder payloads to launch 2014
by M5AKA 20 Jul '13

20 Jul '13

It was announced during the QB50 presentation at the AMSAT-UK International Space Colloquium that two CubeSats, one carrying a SDX linear transponder for SSB/CW, the other a FM voice transponder, should be launched into a 600 km orbit in the first half of 2014. Seehttp://amsat-uk.org/2013/07/20/qb50-amateur-radio-transponder-payloads-t… Live Webcast of International Space Colloquium this weekend http://amsat-uk.org/2013/07/18/webcast-of-international-space-colloquium/ The Colloquium schedule (times in BST, GMT+1) can be seen at http://tinyurl.com/2013ColloquiumSchedule ---- 73 Trevor M5AKA AMSAT-UK website http://amsat-uk.org/ Facebook https://www.facebook.com/pages/AMSAT-UK/208113275898396 Twitter https://twitter.com/AMSAT_UK ----

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