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

Primetec PrimeSat Contoller
by Dave Aitch 16 Oct '07

16 Oct '07

The PrimeSat Controller is a complete and automatic controller for Satellite Communication Stations. When there is the need to communicate by voice or data through a circular or elliptical, low or high orbit satellite, it is absolutely essential to have a continuous adjustment of the antennas and station operating frequencies, in order to guarantee the best alignment and RF signal, as also the correct frequency compensation due to Doppler effect. http://www.primetec.pt/products.php?sec=2&cat=3&prod=12&lang=en Mail direct for any questions. Prefer to sell in the U.K. For sale @ £150:00 Cheers, Dave.

1 0

Re: Moon Missions are possible
by Ransom, Kenneth G. (JSC-OC)[BAR] 16 Oct '07

16 Oct '07

If we are forgetting about the rocket contest would it not be simpler to toss the camera idea all together too? The cost for the Russian lunar fly by trip is $100 million per person (Source http://www.spaceadventures.com/index.cfm?fuseaction=Lunar.Details). I would be really surprised if they would crack the hatch to toss a satellite and remember that human space flight certification is not simple. Might want to forget that idea too. If NASA is going to the moon in 2010, AMSAT better have someone submitting proposals to the design team building the landers NOW! It takes about 3-4 years to get through the process and you'll want to be fully integrated instead of a last minute add on that can also be a last minute removal. It will be a much easier road to be part of an unmanned craft. Bob can tell you how much fun it is to certify hardware for a manned space flight. Human spaceflight certification is not simple. How do you aim the gain antennas once the lander is down? I presume it matters greatly where the lander is on the moon as to how complex the aiming mechanism will be. As you state, power is the biggest challenge. Need to find that out soon before plans can really move forward. Too bad we didn't get in on the SELENE project from Japan (http://www.jaxa.jp/projects/sat/selene/index_e.html), we'd be in orbit around the moon now. Kenneth - N5VHO -----Original Message----- From: amsat-bb-bounces(a)amsat.org [mailto:[email protected]] On Behalf Of MM Sent: Tuesday, October 16, 2007 6:47 AM To: Ric Letson, NB2E; amsat-bb(a)amsat.org Subject: [amsat-bb] Moon Missions are possible Here is my 2-cents. Forgot about the rocket contest. Building a rocket to fly and land on the moon is beyond most of our capabilities. The amateur radio community has very limited funds and only ~2 million users world wide. My suggestion for getting to the moon is to Piggyback on someone else's rocket. Just like we have been doing for years with Arian and Leo-sat applications. Lets plan on going to the moon without the contest. NASA is going to the Moon starting in 2010-2015 with Unmanned landers. So, why build a rocket and lander when we can hitch a ride on the NASA lander. Look at all of the money we can save. No rocket, No navigation, No controlled lander. All we have to worry about is getting a cube sat size box to pass the tough nasa flight saftey requirments. And we could have it running in 5 years or less from the moon. Keep It Simple Details. Camera: Re-use NASA existing lander cameras and use those to send back to earth a few SSTV or digital images via Amateur Radio. When ever possible, reuse existing hardware, do not redesign the wheel. Transmitter: A simple Mode B / J Transponder (2 meter and 440), for SSB/CW. Sorry the moon is too far away for FM. We can copy the Analog Transponder circuits for AO-10. The A0-10 satellite is still running when it has good sun, so that proves the concept of the stable Analog circuit. Avoid DSP and complex digital circuits, Radiation will kill them. I chose Mode B and J becaue this is the most popular format, its what the hams want! We do not want GHZ! Antennas: If possible try to reuse the existing antennas from the Lander. If not, then stuff on a pair of 9 dBd Helix loops. Power: Here is the hard part. I still do not know what the plans are for providing power to the landers. If it's Nuclear, Great, we will have power for 24/7. Solar panels would work for 14 days per month. If its battery only, we are kaput. As for the contest, If some billion dollar university wants to take on the project, Great. The ham community can design the transmitter and focus on what we do well and leave the rest to the billion-dollar university. Other deep space Flights: There are some Russian companies looking into the possibility of Moon-Flyby-Tourist rockets. Tourist can pay $50 million and then fly to the space station. After a few days on the space station, they will then fly to the Moon. They will not land; they will just do a few orbits and then return to earth. Now we will have the opportunity to put ham gear on the Tourist rockets and maybe even toss a ham satellite out the door from Moon Orbit. 73 Miles WF1F www.marexmg.org ________________________________________________________________________ ____________ Shape Yahoo! in your own image. Join our Network Research Panel today! http://surveylink.yahoo.com/gmrs/yahoo_panel_invite.asp?a=7 _______________________________________________ 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

1 0

Re: LEO in Europe
by John Mock KD6PAG 16 Oct '07

16 Oct '07

I have had considerable experience in the 'States in mode J-FM, including operation under challenging circumstances while traveling by car on my Southwest trip earlier this year. I got back recently from two weeks in France. I also made another trip to France two years ago. My experience on both trips was that i found mode J-FM was definitely more difficult for me overseas. There were a number of things that made it seem alot harder for me. First, many stations in/near Europe seemed to want to do a full four-way exchange rather than the often abbreviated form that i often hear in the 'States. Here, my experiences is that when two stations already know each other, or they know the satellite is particulary busy, they will just quickly give their calls (often in quick phonetics) and maybe the grid square in four characters if they haven't said it recently. On the other hand, overseas, the exchange is six characters and appeared to take alot longer. So alot fewer stations seem to complete QSOs during the passes i tried to work than i experience at home. This seemed further complicated by language barriers. While most stations seemed to speak some English, on the average, it did not sound like their primary language. So folks necessarily had to speak slower and repeat things more often. Third, the passes that i tried to work seemed alot busier. I gave up on weekend passes on my last trip, as even on SO-50, i couldn't seem to get a word in edgewise. With a 10 minute walk to where i could find a decent horizon, it just wasn't worth the effort. The weekday passes i worked were better, but they still seemed to me to be as busy as the transcontinental passes over the 'States on weekends. Fourth, there did seem to be more stations who either seemed to be calling without being able to hear the downlink, or perhaps heard it poorly enough that maybe they could only work the strongest stations??? It's certainly something i've experienced alot in the 'States, but usually it's only one or maybe two stations on a given pass that seemed to have that problem. Finally, i didn't seemed to know how to get people to answer me. In the 'States, one just transmits their callsign and grid square, and people answer if either seems unfamiliar. That didn't seem to work for me (but then again, i wasn't hearing my own downlink very often). Was it just a matter of too much competition??? After all, i was only running 1W or maybe 2W, which usually works fine in the 'States. Did i need to call CQ?? I was reluctant to do that, as at home, unless the bird is very quiet, calling CQ usually a clear indication that one is a neophyte and can't hear the satellite. I'm really not sure how to increase my success rate while in Europe. Next time i'm overseas, i'll certainly try again. But only if i don't have to walk very far to do a satellite pass. *SIGH* -- KD6PAG (Networking Old-Timer, Satellite QRPer) [Note: If i'm in your address book, please replace 'qsl.net' with 'amsat.org'.]

1 0

latest AO-7
by w7lrd＠comcast.net 15 Oct '07

15 Oct '07

This morning I worked AO-7, it was clipping quite alot with absolute minimum power. -- 73 Bob W7LRD AMSAT member 28498 Seattle

2 1

Re: how about an amsat moon mission?
by Ric Letson, NB2E 15 Oct '07

15 Oct '07

"It also seems the cost of hardware (HD cameras, still cameras, video transmission hardware...) and getting there would eat up a bunch of that prize money." Kenneth - N5VHO I see some huge obstacles that would need to be overcome before an undertaking like this could be even considered. Then again, amateurs are well known for being able to overcome obstacles set before them. The first obstacle I see is whether you can land the craft on the moon, perform necessary diagnostics and then complete all the required tasks during a single lunar day (14.5 days on earth). More specifically you should be aiming for completing the tasks in the early part of the lunar day when the sun is at a low angle. Temperatures vary from 138C during the peak of the lunar day to -153C during the dead of lunar night. I don't even want to think about a temperature swing 14 days long with a variation of ~290C. (I'd stay away from aiming for that $5Million bonus based on surviving lunar night and just say that if it happens then we surpassed our own expectations) The second obstacle is the selection of individual components. What electrical storage device (NiCd, NiMH, LiIon, Capacitors, etc) are you going to use that will survive the temperature and hard vacuum of the moon? What capacitors, resistors, IC's and other components are going to be durable enough to perform? The vacuum present on the moon is many times greater than that present at Low Earth Orbit, so great that there are few vacuum chambers on earth that can even come close (10e-15 atm or 7.6 × 10e-12 torr). At this level of vacuum plastics & rubbers degrade fairly fast due to outgassing, this includes the materials that our components would be made from. I'm sure AMSAT has engineers that handle component selection based upon environmental conditions (or lack of environment, hi hi) but it's still something to take into account. The mooncast that is required for receiving the grand prize includes transmission of High Definition video from the moon to be received here on earth. Even if we aimed to provide the lowest of the HDTV resolutions (720p) we're looking at a real-time data rate of 7-15MBps. I think this part of the requirement is feasible only because there's no requirement for the video to be transmitted in real-time, so we could theoretically store the video locally and retransmit it at a lower data rate. (Anyone want to discuss data rate vs. required RF bandwidth? Available frequency bands, or the square inverse law and the power necessary to get the signal to earth?) There is a separate requirement for near real-time video but it doesn't specify that it has to be in color nor does it specify a frame rate. Wonder if they'd consider a black & white stream at 2 or 4 frames per second to be "video". The 360 degree panorama of still photographs could be taken with the same camera that's being used for the HD transmission. Just pull stills at specified intervals as the camera and / or craft does a 360 on the surface. In order to cut this post short and summarize my opinion, yes I think that the goal is attainable and within the realm of possibility considering the experience that the various AMSAT teams possess but it would monumental even compared to the launch and operation of Eagle. Ric Letson, NB2E nb2e(a)amsat.org

1 0

RS-22 Loud and Clear
by Keith N4ZQ 15 Oct '07

15 Oct '07

Excellent slow CW telemetry signal on 435.352 (+/- Doppler) from RS-22 this morning at 13:16 UTC on the east coast of the states. Not sure what the output power is from the satellite, but the copy was very easy on a 19 inch 2 meter whip. RS22 UBS 138 IBS 22 USUN 0 ISUN 0 ITXA 0 ITXB 0 TTXA 108 TTXB 107 TNAP 107 TCTR 108 TSBA 105 TSBB 86 MODB 129 MODC 6 MTX 163 MRX 32 RS22 UBS 139 IBS 20 USUN 147 ISUN 81 ITXA 0 ITXB 0 TTXA 109 TTXB 107 TNAP 108 TCTR 108 TSBA 106 TSBB 86 MODB 129 MODC 6 MTX 163 LOS Anyone direct me to a web page or program that will decode the telemetry into some meaningful information ? The AMSAT page does reference any under Satellite Detail. GL Keith N4ZQ FN33

3 2

Re: Gray vis-a-vis Grey
by Ronald Long 15 Oct '07

15 Oct '07

Trevor, M5AKA wrote: >Now my Colour Pallete says Grey, I'm running Microsoft Windows in England so >it must be the right spelling hi. A belated check of my dictionary confirms that you are correct and I am embarrassed. So it's greyline or grayline, British or American, or your choice. ron w8gus

2 1

...and the good news is ...
by John Hackett 15 Oct '07

15 Oct '07

Ladies & Gentlemen, The good news is that AO-7's mode-B transponder was "almost" back to normal this morning. That is to say, signals were *MUCH* stronger than they have been for the last 7 days "outings" in mode-B ... though I did experience some clipping. Presumably, AO-7 has 'also' been suffering from a bout of influensa ... it being that time of year and all ... (It's all that spacedust in the bronchial 'tubes'.....GM1SXX). Of course, it has absolutely nowt! to do with the fact that the old girl was plodding along the "right" side of the blue "Weggie" line. 73 John. <la2qaa(a)amsat.org>

1 0

Help using WISP and Pkunzip
by K7WIN - Jeff 14 Oct '07

14 Oct '07

I don't know if this is the right place for asking for help using WISP. If not please let me know. I have WISP installed and working properly except I cannot seem to get pkunzip to unpack files after downloading them from GO-32. 1. I have verified that the WISP working directory (in my case d:\WISP) is in autoexec.bat 2. I have verified that the pif files are in the WISP working directory. 3. Pkunzip.exe, pkzip.exe are both in WISP working directory 4. I have checked the pif files and the working directory is blank, cmd line is pkunzip.exe I am not sure what else to check and any help is surely appreciated. 73, Jeff - K7WIN

3 4

Ham Radio Video You Don't See Every Day
by JoAnne Maenpaa 14 Oct '07

14 Oct '07

Hi Everyone, While not satellite related per se, a fun ham radio video is at this link: http://www.youtube.com/watch?v=vBGIdf0VjQ4 -- 73 de JoAnne K9JKM k9jkm(a)amsat.org

1 0