October 2007 - AMSAT-BB - mailman.amsat.org

GB5OSO active on 4th October 2007 on Sats & HF
by Robert Turlington 03 Oct '07

03 Oct '07

Starting at approx 0800utc until 2300utc 4th October 2007 GB5OSO will be active on all suitable analogue Satellite passes and HF 14.280+- Qrm to celebrate the 50th anniversary of the worlds first artificial earth orbiting satelliteRegards Robert G8ATE _________________________________________________________________ Feel like a local wherever you go. http://www.backofmyhand.com

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AO-51 / Sputnik Event
by Clint Bradford 03 Oct '07

03 Oct '07

>>...and have extended the event until approximately 1330 UTC October 4th... >...Hey, that screws up my schedule... Wow...Europeans complained earlier today that they were left out of this event - and Andrew spends hours of his day coordinating European stations to accomodate them. Maybe we should be a little more vocal with our own, personal events on this list, because, David, I do not remember seeing a post from you about your event. And Andrew asks us EVERY MONTH for suggestions for the following month's AO-51 operating modes. Clint Bradford, K6LCS 909-241-7666

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Keep It Simple, MM---One more comment
by Frank H. Bauer 03 Oct '07

03 Oct '07

Miles, I did not catch this item in your posting. I think you are about a decade off. We used 386 CPUs on our spacecraft in the mid-1990's. Reference---XTE and TRMM. We are WAY past that technology---several generations. When it comes to parts selection, you have to be very careful on what you use as some parts are more resilient to SEUs and radiation. But I have seen some of the best from the AMSAT community in this department. 73, Frank, KA3HDO "In 2004 ago I was visiting NASA Goddard and I was talking to an engineer building a new communications satellite. I asked him "What CPU and OS do you use". He responded, "We use Intel 80386 and our own Operating System". He said, the 1.5-micron technology of the 80386 is more radiation resistant than the new Pentium CPU's." ------------------------------------------- From: "MM" <ka1rrw(a)yahoo.com> To: <amsat-bb(a)amsat.org> Sent: Monday, October 01, 2007 5:06 AM Subject: [amsat-bb] Keep It Simple, MM Keep It Simple Silly KISS By Miles WF1F The direction of this tread is caution. I am not suggesting that we do not use digital technology for satellites, just that we need to be careful of the technology. The Space environment is not kind to digital circuits. Digital circuits are easily corrupted by solar radiation and thermal stresses. A digital circuit designed for use on Earth many not survive the rigors of outer space. This is partially because of the Size of a transistor inside a modern CPU. In 1978 a computer transistor was made up of wires 3 microns in size. Today's CPU Itanium, uses wires 0.18 microns in size. The new DSP chips used on Digital radio will be some where in-between. With the wire sizes in the 0.20-micron range, it's much easier for solar radiation to cause temporary shorts, which can cause system crashes. In 2004 ago I was visiting NASA Goddard and I was talking to an engineer building a new communications satellite. I asked him "What CPU and OS do you use". He responded, "We use Intel 80386 and our own Operating System". He said, the 1.5-micron technology of the 80386 is more radiation resistant than the new Pentium CPU's. On the Mir Program, we noticed that simple Off-the-Shelf TNC modems seemed to only have a life space of 2-3 years before we began to notice Frequent Lockups and other strange issues. On ISS, a year after we activated the second PacCom TNC, it began to lock up almost weekly during its last month of operation. The Kenwood TM-D700 on ISS ran ok for three years until it was discovered there were some anomalies in the software settings. The radio was taken off Public access for a year until the crew was given time to do a manual partial reprogram of a few channels. Neither the cause of the anomalies or the extent has been determined. One of the ISS crew was allegedly asked once, "What do you do all day", he allegedly said, "Reboot computers" They have 50 laptops on ISS. In closing Use caution in your designs. Keep It simple. A small satellite that does one or two features is better than one big satellite that does 10 big features. The more transistors, the more points of failure. Axle lead Resistor and through-hole mounting of components are much more resilient in space than surface mount components. Hardware is not your only problem; you also need to Extensively Test the software that runs the satellite project. You can never do too much Testing. The Analog satellites AO-7 (launched Nov 1974) and AO-10 (June 1983) are still there when the sun is shining. 73 Miles WF1F www.marexmg.org

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Terrestrial QRM on AO27 2100z pass
by DOBarrows＠aol.com 02 Oct '07

02 Oct '07

Tonight I heard two sources of QRM that didn't seem to belong. The first was a woman speaking in Espanol. I could only recognize a series of digits in part of the transmissions somewhat reminescent of the "numbers lady" on 75 meters back in the late 1960s. Get out your decoder rings. The second source of QRM was a pretty normal USA sounding guy talking to his friend. At this point, I felt competing urges - just listen and try to get a call sign or try to get in over his signal. I could see the time of the pass ticking away so I answered some else who was looking for a AO27 contact. Dave W8IJ Camp Hill, PA ************************************** See what's new at http://www.aol.com

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FT-736R IF Panadapter?
by Dave hartzell 02 Oct '07

02 Oct '07

Hi all, Just wondering if someone has ever tapped the 13.69 MHz receive If of a Yaesu FT-736R. This looks doable on the schematics, but I haven't opened the chassis yet. I'd like to use an SDR-IQ for this... Thanks, Dave n0tgd

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Re: AMSAT-BB Digest, Vol 2, Issue 617
by Clint Bradford 02 Oct '07

02 Oct '07

Don't forget our own AMSAT-NA Web site - it has audio clips of Sputnik, too! http://www.amsat.org/amsat-new/satellites/sounds Clint Bradford, K6LCS / KAF3359 909-241-7666 > With the 50th anniversary of Sputnik this Thursday, I've added to > W0RPK's list of interesting sites on the Internet along with a > couple of our member's reminiscences for publication in our local > contesting club (Potomac Valley Radio Club) newsletter.

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ao-51 on Thursday
by Robert Turlington 02 Oct '07

02 Oct '07

Looking at the ao-51 sked and various postings on the BB, I assume that the only hams that will hear the D/L are in NA presumably the transponder will be off for the rest of the WorldRegards Robert G8ATE (GB5OSO) _________________________________________________________________ The next generation of MSN Hotmail has arrived - Windows Live Hotmail http://www.newhotmail.co.uk

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Re: ao-51 on Thursday
by Andrew Glasbrenner 02 Oct '07

02 Oct '07

Essentially correct unless a EU station willing to retransmit the Sputnik audio message on L band steps forward. Before and after the period posted the satellite will be available in the normal V/U repeater mode. 73, Drew KO4MA -----Original Message----- >From: Robert Turlington <rob_g8ate(a)hotmail.com> >Sent: Oct 2, 2007 11:39 AM >To: Amsat Buleitin Board <amsat-bb(a)amsat.org> >Subject: [amsat-bb] ao-51 on Thursday > > >Looking at the ao-51 sked and various postings on the BB, I assume that the only hams that will hear the D/L are in NA presumably the transponder will be off for the rest of the WorldRegards Robert G8ATE (GB5OSO) >_________________________________________________________________ >The next generation of MSN Hotmail has arrived - Windows Live Hotmail >http://www.newhotmail.co.uk >_______________________________________________ >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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New NASA Slogan
by Clint Bradford 02 Oct '07

02 Oct '07

WINNER: Exploring Other Worlds, Understanding Our Own 2nd NASA: Explorers Wanted 3rd NASA: Bringing the Universe to Your Doorstep And the one that made me laugh the hardest: NASA: We Find Your Lack of Faith Disturbing http://blog.wired.com/wiredscience/2007/10/and-the-winner-.html Clint Bradford, K6LCS

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Re: Keep It Simple, MM
by Dave Taylor 02 Oct '07

02 Oct '07

Miles, you know better than this. The D700 problem has nothing to do with being in space. It was caused by a crewmember making unauthorized changes to the D700 programming while playing with SSTV. -- Dave, W8AAS On Oct 1, 2007, at 8:06 AM, Miles WF1F wrote: > The Kenwood TM-D700 on ISS ran ok for three years > until it was discovered there were some anomalies in > the software settings. The radio was taken off Public > access for a year until the crew was given time to do > a manual partial reprogram of a few channels. Neither > the cause of the anomalies or the extent has been > determined.

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