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

Re: The Moon is our Future
by MM 02 Jul '09

02 Jul '09

>From WF1F: Yes, that is one of the many challenges we have to plan for. 14 days of pure sunlight (Lunar-Day) and 14 days of freezing darkness (Lunar-Night). We also have some unknown questions about our power source. Will we be able to run during the 14 days of darkness or will we be operating during the Lunar days only? What I mean by Simple, is the design of the transponder needs to be Simple (KISS). Strictly analog circuits for the transponder, NO DSP, NO CPU’s, No SDR to run the transponder. We need the reliability of the AO-10 transponder and not the complexity of AO-40. --- On Thu, 7/2/09, Nigel Gunn G8IFF/W8IFF <nigel(a)ngunn.net> wrote: > From: Nigel Gunn G8IFF/W8IFF <nigel(a)ngunn.net> > Subject: Re: [amsat-bb] The Moon is our Future > To: "MM" <ka1rrw(a)yahoo.com> > Cc: kg4zlb(a)gmail.com, amsat-bb(a)amsat.org, "Jack K." <kd1pe.1(a)gmail.com> > Date: Thursday, July 2, 2009, 8:56 AM > There is nothing simple about a > project that can withstand the extreme temperature changes > and eclipse periods that exst on the moon. It's probably the > most hostile environment we're likely to build for. > > > MM wrote: > > > A plan for a simple transponder (KISS no complex > P3E). >

1 0

Re: Antenna Question
by Jim Jerzycke 02 Jul '09

02 Jul '09

I'd have to say "It Depends". A 'regular' QHA has about zip for gain on the horizon where you really need the it, although I've read where the "extended" QHA's have a 'flatter' pattern, with the gain squeezed down towards the horizon. Same with eggbeaters. I have a pair of the M2 units, and even with good quality preamps, they leave a LOT to be desired on low-elevation passes, which is what most passes wind up being. Jerry, K5OE, has a modified eggbeater-II design that pulls the pattern down towards the horizon quite a bit. I built a pair of these years ago, and they seemed to work well. Unfortunately I no longer have them, so I can't do an "A-B" comparison against my M2 units. An altenative would be to build a Lindenblad like Tony AA2TX designed. I have the parts collected to do just that, but won't have the time to build one for a few weeks. 73, Jim KQ6EA --- On Wed, 7/1/09, Steve Bluemel <stevebluemel(a)gmail.com> wrote: From: Steve Bluemel <stevebluemel(a)gmail.com> Subject: [amsat-bb] Antenna Question To: AMSAT-BB(a)amsat.org Date: Wednesday, July 1, 2009, 5:17 PM Hello All, Just a quick Question. Quadrifilar Helix or Eggbeater? All other options considered, which would you chose? Thanks! Steve KI6OQU _______________________________________________ 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

2 1

QSL card?
by Scott Smith 02 Jul '09

02 Jul '09

Hi, has anyone received there QSL card from Richard Garriott? when he was aboard the ISS?. 73 de VE6ITV Scott

5 5

Unused sats
by Howie 02 Jul '09

02 Jul '09

While the opportunity to ride share on a GEO sat is probably our best chance at a HEO transponder, it is still a very slim chance in my opinion. I have worked in the commercial satellite industry for over 25 years and the most valuable piece of real estate in existence is located in the Clark Belt. Commercial satellites are very much a "for profit" business and every watt of power and ounce of weight has a dollar value beyond comprehension. Even if we offered to pay our share of weight and power, it would not be enough because the loss of return on investment for the non revenue generating "hitch hiker" must be factored in as well. I now work for a subsidiary of the second largest satellite operator in the world who is expanding their business to offer "hosted payloads" to customers who want to orbit specialized payloads without having to launch their own satellite. One of my co-workers was invited to participate in a meeting of the group working on this offering. When I found out, I suggested he bring up the idea of launching a very small amateur payload as a demonstration of the great utility that can be achieved with a very small, cost effective payload. He did and the response was "You mean for free ?" He was never invited back. If we want to get on a commercial sat, we need to have something to "sell", i.e. a good reason for them to orbit something that may help them generate revenues in the near future. I can say with reasonable confidence that an analog bent pipe transponder will not be very interesting. Something along the lines of the Advanced Communications Package might. Even though I was not a big fan, the P-25 over satellite might be another good one if we could prove a good scenario. If we want a ride into HEO, we need to earn it. Howie AB2S

5 4

Re: qsl card
by Scott Smith 01 Jul '09

01 Jul '09

Tnx folks, i'll keep wating like the others, guess he must be quite busy. 73 de VE6ITV Scott

4 3

NASA Kills Ulysses
by Clint Bradford 01 Jul '09

01 Jul '09

After 18 years of operation, NASA has switched off Ulysses, the space probe designed to study the properties of solar wind, the heliosphere magnetic field, and the solar radio bursts that can greatly affect our gadgets, telecommunications, and every electronic system here on planet Earth. It was the first object to see and study our Sun's poles. Read Ulysses Mission Operations Manager Nigel's email message to the Ulysses community ... http://tinyurl.com/mvneu4 Clint Bradford, K6LCS 909-241-7666

7 7

Antenna Question
by Steve Bluemel 01 Jul '09

01 Jul '09

Hello All, Just a quick Question. Quadrifilar Helix or Eggbeater? All other options considered, which would you chose? Thanks! Steve KI6OQU

1 0

Re: NASA Kills Ulysses
by Armando Mercado 01 Jul '09

01 Jul '09

Hi All, The title of this post paints an inaccurate picture of this joint ESA/NASA mission. Ulysses power supply (RTG) is not producing enough power anymore to run its instruments and heaters to keep its propellant from freezing. Ulysses was due to be retired last year, but controllers devised a clever method of firing its thrusters every 2 hours to keep things warm. The tanks are virtually empty now. Also its X-band transmitter failed leaving only it S-band transmitter running at 512 bps. Ulysses is currently 5 AU from earth with a 45 min. 1-way light time..to far away to act as an amateur communication satellite in its decommissioned after live, but it's an interesting mental exercise. See the follow for more: http://www.esa.int/esaCP/SEMWHF1P0WF_index_0.html > Date: Wed, 1 Jul 2009 09:00:01 -0700 > From: Clint Bradford <clintbrad4d(a)earthlink.net> > Subject: [amsat-bb] NASA Kills Ulysses > To: amsat-bb(a)amsat.org > Message-ID: <B95E6E7F-69B9-49F0-B639-ACD8527B1D87(a)earthlink.net> > Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes > > After 18 years of operation, NASA has switched off Ulysses, the space > probe designed to study the properties of solar wind, the heliosphere > magnetic field, and the solar radio bursts that can greatly affect our > gadgets, telecommunications, and every electronic system here on > planet Earth. It was the first object to see and study our Sun's poles. > > Read Ulysses Mission Operations Manager Nigel's email message to the > Ulysses community ... > > http://tinyurl.com/mvneu4 > > Clint Bradford, K6LCS > 909-241-7666

1 0

Kenpro-Yaesu 5400 5600B question
by bpn518＠aol.com 01 Jul '09

01 Jul '09

Good day sat-guys: I have an old Kenpro G5400 without computer interface and a newer Yaesu G5600B control box. What are the differences in the motors between these 2 series other than the limit switches? In case of the control boxes, I see the G5400 has starter motor caps, but the G5600B control box doesn't. The old motors didn't work with the 5600B box until I added a starter cap to both the AZ and EL motor lines. I am planning to use the 5600B box with LVB tracker- any other issues? What do I need to do to use my old motors with the G5600B? Or, anyone have 5500 motors that they wish to sell? Any assistance would be appreciated. Thanks, Bennett ko2ok

1 0

AO-51 Telemetry
by Gould Smith 01 Jul '09

01 Jul '09

The AO-51 telemetry archive is up to date as of last night. AO-51 telemetry data is available in raw format, CSA (comma separated variable) format that has the channel data converted by the configuration equations and there are some Excel files (most with graphs). There are a number of Excel files with graphs for June 2009 as that was a very interesting month for AO-51 operation. The telemetry archive can be found at http://www.amsat.org/amsat/ftp/telemetry/ao51/ I encourage exploration of the data and any insights gleaned. 73, Gould, WA4SXM AO-51 Command Station

1 0