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Space

Ham Satellite Suffers Failures, Is Silent 79

Posted by michael from the sounds-of-silence dept.
Bruce Perens writes "The Phase 3-D satellite, renamed Oscar 40 once it reached orbit, has suffered multiple failures and has stopped transmitting telemetry. It is not yet known if the satellite is responding to commands. The main telemetry beacon on 145.898 MHz was operating poorly after separation and now may be transmitting a weak unmodulated carrier. A fuel valve appears to be sticking closed and appeared to be only 10% open after multiple operation commands. Then, the first flight burn was 3 minutes too long due to another, not-yet-understood problem, boosting the craft into a higher orbit than expected (not yet a problem in itself as the final orbit is to be even higher). A backup flight computer, itself an experiment to see if the CPU would be radiation-hard enough to survive, has its RAM corrupted every 1 or 2 days in orbit as it crosses radiation belts and currently is not set up to reboot automaticaly. The primary flight computer may have crashed. An expected watchdog timer reset did not occur, but this would be the case if the satellite was receiving some commands."

"We may have to wait until after Christmas for another reset. Controllers have not transmitted a hard reset command yet, which would work even with the flight computer crashed, as they wish to explore other options. The satellite would automaticaly cycle through a number of frequencies and antennas if it does not get any commands for 10 orbits, and controllers hope to re-establish control as this happens. A hard reset could delay that option.

"The satellite waited several years for launch due to Arianne 5's early failures and a revised accelleration profile for the booster that required a redisign of the satellite frame to take additional stress. Aging may have effected components such as the fuel valves. Telemetry stopped suddenly during work on the 400 Newton kick motor, leading to speculation that the satellite may have suffered physical damage, but NORAD radar profiles indicate that it has not exploded.

Problems with Phase 3-D are bad news for hams, who raised $1 Million for the satellite, the 40th in the series of Amateur satellites launched since 1962. Phase 3-D has been criticized for pu ting too many eggs in one basket, unlike other small ham satellites built on a low budget and more easily launched as hitch-hikers with other payloads than the multi-ton Phase 3-D.

"The core development team urges patience. The satellite is in a stable orbit in one piece, just where it is expected to be, as confirmed by NORAD. They can take lots of time to debug it where it is, and hope to restore its functionality.

"For bulletins, see the AMSAT web site.

"A number of other ham satellites remain operational, and astronauts are currently using a ham station on the International Space Station to speak with people on the ground."
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Ham Satellite Suffers Failures, Is Silent More

Ham Satellite Suffers Failures, Is Silent

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  • A hard reset would be physically turning the system off and on again.

    ctrl-alt-delete is a soft reset.
  • How quickly do bits get corrupted? I would have thought that with a load of error correction and a device continually fixing things up again would grant you quite a bit of stability© Really there isn't anything preventing storing 128 bits¥or more for every byte© If any go wrong they should be correctable before the byte becomes unrecoverable© The only thing that this wouldn't help is if bursts of radiation take out all of the data very quickly, Is this what happens?

    I would also have though that the same should go for processors© If you sent up a satelite chock full of FPGA's ¥presubably with every cell containing a lot of redundancy on their state memory you could make work arounds for many failures, lik say a NASA Screwdriver going through one of the PCBs©

    How well can the radiation conditions of space be replicated on earth for testing tis sort of thing?

  • For linux users, a computer being frozen means that Windows basically stops responding to all input, including mouse and keyboard. It's actually kind of a cool phenomenon, you should try running windows for about 30 minutes just so you can see it for yourself.

    Linux does this too. I've had various linux installations lock up hard. It's generally due to bad hardware, or a hardware conflict. This is true on windows as well, however. Also, linux may kernel panic (I've had my FTP/shell box do this twice since I installed it three weeks or so ago) and if you're in X, it may look like the box has just hung, depending on your video card.

  • This thing really isn't lost yet. (Score:3)

    by fwc ( 168330 ) on Friday December 22, 2000 @04:50PM (#542723)
    My understanding, being an amateur radio operator (among other things) and following this closely for the last week or so since launch, is that this satellite was designed in such a way that it automatically goes through some error-correcting procedures, such as changing radios and frequencies for telemetry and command transfers, etc. etc. etc. However the complete cycle takes days, not hours, and as such, the people at AMSAT decided to give it a chance to recover before trying more drastic means.

    My understanding is that they also have the equivalent of the "big red power button" or "control-alt-delete", which they haven't even started to try yet.

  • Plus, when you increase the amount of metal shielding around electronics, you start to get a small amount of radiation from *that*.
  • No offense, but just when did manufacturers start making SSB handhelds?

    In 2000. I guess you haven't seen this [yaesu.com]! 1.8 MHz through 450 MHz, all modes, self-contained AA batteries, and OK it's got a shoulder strap, but it's a handheld.

    And no, I haven't missed articles on working satellites via FM. That's what I was talking about.

    People can set their own challenge levels, and if they are interested they work from low to high. Having an easy satellite mode would have been a great starter for beginners and especially young people. You know young people, they look like other hams, but aren't bald with a limp :-)

    People gave me the same argument about packet in the 80's, which came down to where's the sport in that? Not everybody is into Amateur Radio for the sport.

    Thanks

    Bruce

  • They should have consulted with Pizza Hut for better funding, like the Russians did.

  • I've got $20 that says that MIR hits Earth before this thing does! Any takers?

  • UPDATES (Score:5)

    by Bruce Perens ( 3872 ) <bruce@perens.com> on Friday December 22, 2000 @08:44PM (#542728) Homepage Journal
    Someone please moderate this up. Here are the updates to this story.

    The RAM corruption on the experimental backup flight computer is a normal feature until the EDAC software "scrubbing" routine is enabled. This constantly scans RAM for errors and corrects them before they grow too large to be correctible. That software has not been loaded yet.

    The 145.898 beacon was not damaged, a 440 MHz one was. The 145.898 beacon runs from the backup flight computer while the 440 MHz one runs from the primary one. That's why the backup flight computer could cause a loss of telemetry.

    There have been a good deal more than 40 Amateur satellites, only the ones that actually reached orbit and transmitted get numbers, and there are Amateur satellites outside of this numbering series.

    Insiders tell me to relax, have patience, and that it is really jumping the gun to think the bird is lost.

    Thanks

    Bruce

  • I was with you until the "Maybe the jews deserved to be cooked,..." comment. Personally I don't care if you're fat, disabled and gay, but the "jews deserved to be cooked"? Please. I'm not even Jewish and I'm offended.
  • And PANSAT from the Naval Postgraduate Institute in Monterey, California is similar. I think it was all built by Navy folks, but was promised to be an Amateur satellite using spread spectrum and the software to use it would be made available to Amateurs. That never happened.

    Bruce?

  • Clever little script kiddies here have either crackerjacked my password, or have hacked /. itself. They were even congratulating themselves on how clever this was, on a thread I'd posted to a day ago.

    It's been changed, and shall be changed fairly often, too. Maybe this will help. For those who've read these, you *might* know me well enough to realize that my spelling is darned good, and that I've never been raped, nor have I ever "had" a man, period.

    As for the Jews, that's too sick to comment on. Perhaps I should run this past my ex-boss, one of the nicest men I've ever known, himself Jewish? He may get a mild giggle from it. I'm sure my partner, herself Jewish, would be amazed :)
  • Apparently, there are a great many of us who neither care for, nor wish to be a part of the "action" on Slashdot, which these days has turned into something i'd imagine closer in resemblance to a gay bar than a channel for geeks to use and enjoy. [....] PS.. Be sure and snicker in amusement as an endless stream of kiddies and tyrant moderators take their time to write out a few lovable responses to this post--After all, encouraging geeks to go elsewhere is no fun for them--They'll have nobody to push around! But incase they do, be sure to note their names..Look them up with a handy /whois command next time you're in IRC and decide for yourself the answer to the topic. The rest of us are already sadly aware of the answer.
  • Nope, ctrl-alt-delete is soft....
  • We at the Great News Network present the official transcript from the room where the satellite was being constructed:

    Bubba: "Hey Jeb, you got that there SIMM that I need fer the new sat?"

    Jeb: "Yeah Bubba, Ah got 'er right here... CATCH!"
    (throws 8 MB 30 pin SIMM to Bubba, it bounces off of Bubba's head and lands in a cup of cola)

    Bubba: "Awwww, dang, what are we gonna do now?! The dern thing fell in the pop and sunk in!"

    (Jeb picks up the cup and pours the cola out to retrieve the SIMM)
    Jeb: "Just keep quiet about this, maybe none of them controllers will notice, here, get me that there can of WD-40 to clean this pop up..."


    "Titanic was 3hr and 17min long. They could have lost 3hr and 17min from that."
  • Sorry, maybe I need more sleep, but that's the first thing that came to mind when I saw "Ham Satellite Suffers Failures"... Either that, or more caffeine...
  • Ask NASA, other space agency or people in university labs that research this stuff about proper radiation shielding for processors?

    Actually, NASA and most other space agencies utilize data collected on Amateur satellites. IOW, a lot of the research comes from the Amateur community.

    A Ham satellite might launch with five different types of RAM, each hardened using five different new techniques. The hardened RAM might be donated by various agencies. They get to test their RAM-hardening techniques cheap. The Amateur community gets free space-hardened RAM in exchange for the risk posed by using something not quite tried-and-true.

    I, too, wish them luck. I might even blow the dust off my IC-970H and 22C/40CX!

    de Gus 8P6SM (formerly active on AO10, AO13, AO16, FO20, KO23, AO27)
  • Several years ago I worked for an "engineering service contractor" for NASA, and had the opportunity to design the sensor electronics for a space-based sun-staring telescope, called Solar X-ray Imager. The task would not have been excessively difficult except that the radiation levels expected were quite high, and we had to design it to be very radiation resistant. This proved to be very expensive to do.

    For certain electronic functions, there are radiation hardened integrated circuits. We used a set of CMOS devices manufactured by Harris (now Intersil) which are manufactured using a silicon-on-sapphire technology which makes them tough indeed. (The manufacturer claimed that they were radiation resistant up to "strategic levels" - to run through massive radiation doses and never glitch...) While they were very good parts, their cost was incredible. They were getting US$ 225 for a single 75hc00 equivalent device which usually costs 25 cents. Processors and memories had prices that were proportionally worse. Nobody but government bodies with the power of taxation can afford these things.

    The other method of achieving radiation hardness is shielding. In our case, we had to use this in addition to the radiation hardened integrated circuits, because the telescope sensor itself was not radiation hardened (otherwise it would not have been able to see light either!) The shielding we used was made from tantalum, machined in shapes to cover the sensitive parts. Now tantalum is not inexpensive, it does not machine well, and is heavy. The weight is the limiting factor, since whatever you use you have to launch into space, and the cost per kg is very high. Shielding which is sufficient is also too heavy to launch on a secondary payload.

    My thoughts? Amsat did the best they could within the budget, and the budget (raised from donations) did not provide enough money to use the premium radiation hardened parts everywhere.

    Too bad...

    73 de W4TI
  • This made me curious as to the major storage medium being used in space?

    RAM-disks are common. Cosmic rays and gamma particles cause single-bit errors every few hours, which is why they use 11-bit RAM for EEC and run a software program that "washes" the RAM continually. I don't think this is what they mean when they say ...its RAM corrupted every 1 or 2 days in orbit as it crosses radiation belts... because this single-bit error mode is common and expected. I'm not really current but I don't think any Amateur birds fly with hard disks on board...

    Is heavy shielding a solution for this?

    Heavy is not a good word when you are trying to get something into orbit! :)

    de Gus 8P6SM (formerly active on AO10, AO13, AO16, FO20, KO23, AO27)
  • Tee hee.

    How well can the radiation conditions of space be replicated on earth for testing tis sort of thing?

    You use an X-ray machine, a van de Graf generator, a vaccumm chamber, and so on. It doesn't get you all of the way there, but it can give you some data.

    Thanks

    Bruce

  • Where the hell are you getting this ESA stuff from?

    All they did was sell space on their rocket - The launch itself went perfectly. No evidence of government screwups there.

    The satellite was designed, built, and the launch paid for with private funding. AMSAT is non-profit, but non-profit != government!
  • One problem is the attitude of the satellite. It's probably got the high-gain antennas pointing in the opposite direction from the earth right now, because of the attitude they got it in for the burn. So, when it resets, it's supposed to use optical sun and earth sensors to orient itself. There are torque wheels and/or gyroscopes to do the physical orientation, it doesn't burn fuel for this. But the earth sensor was being blinded by the sun, so that might not work correctly, at least not in this part of the year.

    So, we all cross our fingers.

    Thanks

    Bruce

  • No crackerjack needed, check the user numbers ... Gee, that's lame :) 17812 is me, any other number is not-me. Simply little boys trying to have fun. :)

  • Hey, Bruce? There have been SSB handhelds around since at least the late 1980's. I distinctly remember a couple of 6- and 2-meter SSB handhelds put out by various manufacturers - and they *were* handhelds, about the size of a dual bander today.
  • As I read this article (at +2, no parent -- seems reasonable in most discussions), I'm distraught by the number of posts being displayed by Bruce Perens. Sure, he's (appearently) a smart guy who knows at least enough about the subject to author the article, but why are 10 out of 22 >+2 posts from him?

    Counting the article itself as 1, that's -half- of the displayed posts, which is just silly.

    Either the moderators are favoring Bruce's commentary (which is typically useful, informative, and insightful -- though not without context), or Bruce is using his +1 bonus on every post (which is -not- needed on a three-line message, no matter what it contains).

    As it is, some of Bruce's replies are without displayed parent posts, and in (at least) one instance he appears to have replied to himself (which means there's at least two <+2 posts which need attention).

    Just a random musing...
  • Bruce has explained that the critical onboard computer is rad-hard. The one that has the ram corruption is an experimental unit. The control team was planning on uploading error detection and correction (EDAC) code to deal with the ram corruption.

    Hamsats spend their money where they have to and use clever design to get workarounds where they need it. And we take more risks than the commercial and scientific folks.

    Eyesat/AO-27 (launced in 1993) uses a NEC V50 CPU with EDAC code for a 16MB ram disk. The only rad-hard chips were used for the boot roms, so a reset (either CPU crash or from a reset command) is unlikely to fail. As I recall, those few chips cost a fair percentage of the rest of the satellite's computer.

    I might add that the AMSAT designers are VERY experienced with the space environment. Many work in space-related industries. The primary computer on AO-40 has a design history including two successful predecessors (AO-10, 13). They know what they are doing.

    KA1LM
  • To find out more, go to http://www.amsat.org [amsat.org].
  • Well, I know this is flamebait, but I think this is just his ego trip. He cares about this satellite, and he wants to make sure the rest of us know about it. In one post, he even said, "Someone moderate this up. These are updates to the story."

    He is too arrogant in forcing his interests on us. I agree with him a lot of times when he is discussing free software, but not this time. He should let the community decide what is important and what is not.

  • what they do put windows on it.... this stuff sounds familir http://members.home.net/jessezack/images/320.gif

    kinda rediculus if you aske me..
  • As a ham who's used satellites before, this is awful :( I hope they figure it out soon.

  • whats this for? (Score:3)

    by iAlex ( 134189 ) on Friday December 22, 2000 @02:06PM (#542750)
    Just one question. What is the purpose of this satellite? Are people with ham radios supposed to be able to brodacast back and forth to it or something? I guess I am just out of the loop on this one.

  • Oops (Score:1)

    by Flavio ( 12072 )
    A backup flight computer, itself an experiment to see if the CPU would be radiation-hard enough to survive, has its RAM corrupted every 1 or 2 days in orbit as it crosses radiation belts and currently is not set up to reboot automaticaly.

    I don't want to sound arrogant here, but couldn't they either:

    1. Put a radiation hardened processor instead just like everybody does or...
    2. Ask NASA, other space agency or people in university labs that research this stuff about proper radiation shielding for processors? [I understand this option may be more complicated than it sounds]

    In any case, I wish them luck.

    Flavio

  • *Before* posting! (Score:4)

    by maggard ( 5579 ) <michael@michaelmaggard.com> on Friday December 22, 2000 @02:13PM (#542752) Homepage Journal
    PLEASE - before asking 100 times the same questions regarding Ham sats remember you're on the web. Spend the 30 seconds BEFORE you post and see if you can find the answer yourself.

    Google, Yahoo, Metacrawler, etc. are all more efficient then asking every time someone else to explain it for you.

    ps Also check the links in the article itself.

  • Yup. It picks up signals, usually on one RF band, then retransmits them back again on another. The ones I used to use were the Russian satellites, with an uplink on the 10-Meter band, and a downlink on 2Meters. My station was *way* underequipped to run the 2M / 440MHz birds, and I had no equipment at all any higher than 440MHz.

    The antennas were huge, the feedline expensive, the low-noise preamps finiky, and compensating for the doppler shift as the bird orbitted was, well, entertaining - but it *could* give people a chance to try to talk all over the world (well, over a lot of it, depending on what was visible to the satellite at the time).

    However, once I got a reliable, steady Net connection (640kbps bi-di DSL), my interest in Ham radio rather waned. I gave most of the equipment to a fellow Ham, who was more into that than I was.
  • "Controllers have not transmitted a hard reset command yet, which would work even with the flight computer crashed,"

    Is that like hiting ctrl-alt-delte?
  • Have you ever had one of those days when nothing goes right for you?
  • I think there's at least 50 satellites up there for grabs. Pick your favorite color.
  • Er - depends on your taste in bars.

    Sweater bars (gay equivalent of fern bars) mebbe - leather bars generally not, dance bars "What??? I can't hear you..."

    Actually when I post to /. I envision legions of overly bright just-out-of-highschool students, the ones who can't wait for the question to be asked before shooting up their hands and quivering with excitement 'cause they know the answer (of course 1/2 the time they're completely off base 'cause they didn't actually check to find out if the question asked is really the answer they couldn't wait to blurt^H^H^H^H^H post.)

    Anyway, there's nothing wrong with sometimes encouraging the more clueless to refrain from posting. I mean, EVERY time a noun is used some dimwit has to post "What's a 'noun'" - it's the web fer cripes - LOOK IT UP!

    Naw, gay bars are better behaved & there's a better chance of getting laid.

    Wonder how many will now post "What's a noun"...

  • See, this stuff is HARD! (Score:3)

    by ceswiedler ( 165311 ) <chris@swiedler.org> on Friday December 22, 2000 @02:57PM (#542758)
    Launching stuff into space is a risky and difficult process. All these problems are why NASA used to build triply-redundant probes (Mariners, Voyagers, etc) and then send two or three of them.

    Anyone who's ever programmed on a REAL production system will attest to the fact that it's the last few obscure bugs that are the most difficult to find. The difference between a 99.99% bug-free product and a 100% bug free one is enormous.
  • Actually I saw this phenonenon myself running linux the other day - it just totally stopped responding, and I had to whack the reset button to get any kind of meaningful output from the computer.....

    .... which turned out to be "No keyboard detected, press F1 to continue", so I reached round the back and plugged it back in.
  • Hi again, Flavio,

    The rad-hard CPU of choice for spaceborne equipment is the 1802. Remember the RCA COSMAC personal computer of long ago? I think they have this in silicon-on-sapphire. There are a small number of satellite hackers who still practice 1802 assembler at this late date. It should suffice to say that nobody uses this CPU for anything else any longer. So, an experiment with a modern CPU was very desirable. It looks like the problem might not be in the CPU.

    Thanks

    Bruce

  • Re:Storage mediums in space. (Score:4)

    by IronChef ( 164482 ) on Friday December 22, 2000 @03:02PM (#542761)

    I can actually answer some of this. I used to work at JPL on spacecraft computers, back when I was a EE student. I did stuff like writing bootstrap code in assembler that was particular to the custom chips that comprised the computer. I also designed PCBs for the test platform.

    Space is a brutal environment. Even out in the deep black between the outer planets, there are a lot of gamma rays and charged particles that would play hell with a conventional computer. Spacecraft computers are built of relatively old-fashioned components, and they are made with a special radiation hardening process. There are no 1GHz CPUs in space. We don't really need them, either; the tasks performed by robotic spacecraft are pretty simple, compared to say running Windows.

    Shielding isn't the answer. Imagine a metal box around a computer. Now imagine a proton or some other relatively heavy charged particle is fired into the metal. The particle can hit an atomic nucleus and shatter it, flinging MORE particles into the hapless computer. Bad news. And shielding thick enough to protect against this is heavy, and that's bad for spacecraft too.

    So they use simple, rugged components, that can usually resist a proton zipping through them. And for the times when a bit gets flipped by a particle -- this is called a Single Event Upset or SEU -- there is a TON of error correction & detection bits allocated in these computers. The system I worked on, which is the computer in the Cassini craft, used a modified Hamming code. I think that almost 1/2 the bits in every 16-bit word were allocated to EDAC.

    Unfortunately I do not remember the details of how you fab a chip to be radiation resistant. Some special substrate, special transistors... I'm sure you can Google for it.
  • They were really pushing the technology. The thing has an ammonia arc-jet motor for orbit maintainance. Such a thing has never been tried. That's the smaller motor, the kick-motor is more conventional. And of course there are tons of experiments like orbit-to-ground laser communications, TV cameras, and a full compliment of Amateur radio repeaters. You're supposed to be able to talk through this with a walkie-talkie.

    But yes, this is a large number of initial failures for a ham satellite. Most of them are much simpler. But all of them have things break and they patch around it and go on using the bird. The same is true for commercial communications satellites.

    Thanks

    Bruce

  • I have a nice high-speed connection and still find interest. I've a ground station with azimuth-elevation rotator on dual crossed beams for 145 and 440 MHz. And of course I do regular VHF and HF as well. It's fun to be able to communicate without the internet or a phone network, and the technical skills one can acquire this way are substantial. Hamming is what got me started in a technical career.

    Thanks

    Bruce

  • A backup flight computer without a watchdog timer?

    I believe there is a watchdog timer. It triggers if there is no traffic on the telecommand receiver(s) for ten orbits. Since it's a deep-space bird, AO40 has a long orbital period (mean motion 1.268-ish orbits/day). The watchdog timer will not time out for nearly eight days.

    de Gus 8P6SM (formerly active on AO10, AO13, AO16, FO20, KO23, AO27)
  • My understanding is the controllers had not yet uploaded EDAC code to the IHU-2 computer when the telemetry failure ocurred. That would have solved the RAM corruption problem. And maybe alleviated whatever happened, as they were having problems with the default 70cm telemetry beacon from IHU-1 and were using IHU-2 to activate the 2M beacon.

    KA1LM

  • Re:Open source in action.. (Score:1)

    by Anonymous Coward
    You are correct that the Amateur spacecraft construction process is similar to an "open source" project in that volunteer amateur radio operators from all over the world have been involved in the design, construction, and of course, fund-raising, needed to bring this spacecraft to orbit. Amateurs have built and operated communications satellites since about 1962, hence the number "OSCAR 40" (and not all amateur satellites are in this numbering sequence-there are more than this).

    It is premature to conclude that the spacecraft has failed. This has not been determined and there several steps yet to be undertaken in a recovery process. This is just one, albeit the most complex so far, of a great many "open source" satellite projects. Space projects are a very complex undertaking, and even tougher when done by volunteers on donated $ contributions.

    AMSAT has announced that it will put together a (volunteer) inquiry into what happened, during the next few weeks. There are many speculations as to "what went wrong", but very few based on actual data. It remains entirely possible that controllers will regain control by issuing a hard reset in the near future. After the inquiry is completed, and after all system restarts have been completed, then it is time to make plans for the future.

    Ed, KF7VY
    http://hamradio-online.com [hamradio-online.com]

  • Ahh, but then the karma whores wouldn't have anything to do.
  • The satellite is spin-stabilized until they're done with the orbital manuevering. I don't think any automatic attitude control is activiated until they go into 3-axis mode. The command stations were using the sun/earth sensors and the camera experiment to orient for the first rocket firing.

    But you're right about the satellite attitud. It should be close to 0/270, which poins to high-gain antennas at earth only near perigee (use InstantTrack or similar to see). So they've been using the omnis. I recall that the 70cm beacon was very weak, which is why they switched to 2M (which required IHU-2 I understand, which has the SEU's in ram, ...)

    I'm hoping the watchdog trips on the 25th, or that a reset if necessary is successful.

    KA1LM
  • It has been discovered that AMSAT didn't pay license fees to the RIAA and M$, so the copy protection in the hardware and software turned off the Satellite.
    RIAA and M$ have stated, "We can not allow hacker ham radio operators to steal our intellectual property." They will allow AMSAT Corp access again for 26 Million Dollars for a 1 year license fee.
    They also want to inspect the satellite HD contents because the Napster server says they have a MP3 of Rocket man and a AVI video of the Moon Launch on the HD

    In a related story the FBI has raided the ARRL [arrl.org] ham radio HQ looking for antennas and radios that could be used to listen to frequencies, they also confiscated secret PSK31 transmitters that could be used by spies to send signals to spy agencies.

    Also discovered was a secret world wide system to track people, cars, boats and planes without the knowledge of the passengers. The secret program, called APRS [aprs.net], violates USC 3, 21 and Janet Reno indicated today that all licensed ham radio operators will be investigated. You may remember that the Branch Davidians used ham radio during the seige at Waco.

  • I find them fascinating. I'm surprised we don't see a real investigation about them - or maybe not, considering what they probably are. :-)
  • Bruce Perens wrote
    Sigh. I don't know about you, but this really un-made my day. AMSAT has to be about the bravest amateur experimenter group out there. They envisioned a new day for ham radio powered by a super satellite that would give you worldwide range with a walkie-talkie and a handheld beam.
    No offense, but just when did manufacturers start making SSB handhelds? I must have missed the announcement. (You must have missed KA8IFC's article on working through an early RS (RS-8?) with an HT and a 5/8 whip lo these many years ago.)

    The fact of the matter is that the "brave new world" would still not have appealed to the people that AMSAT is trying to attract because it makes satellite communications about as interesting as walking up to random people at a mall somewhere. Eliminating the challenge of the operation forces people to focus on the fact that what is being communicated isn't all that interesting or earth-shattering.

    I've heard it said that amateur radio is the "national park of the mind" but the people who most often use the phrase don't seem to realize what it means. People don't go backpacking because it's the easiest way to get from one place to another or climb mountains with pitons and rope (or even without) because that's the easiest or even cheapest way to get to the top. No, they do it so that they can feel as if they have accomplished something.

    Working 100 "countries" through Oscar-8 was an accomplishment and worthy of comment and congratulations. Working the fellow on Mir (who I happened to meet a few years back--one of the fringe benefits of being a ham in Houston) was an accomplishment. Working 100 countries through Oscar-40, assuming that they can get it to work (I wouldn't hold my breath because your description makes it sound like no one will get any use out of it even if its command receivers and computers are working) will be something that cause people to yawn. And sending an email to a SAREX TNC proves nothing other than that you can afford the equipment.

    Please don't think that I'm trying to be down on your hobby, or mine, either. I'm simply trying to point out some things that you don't seem to realize, but which seem to adequately explain the extant facts concerning the decline of amateur radio. No, the ultimate evil isn't Morse code, it's the belief by persons such as yourself that the goals that appear most desireable to you will appeal most to potential radio amateurs. It simply isn't so. The coolness factor of Phase-IIID has been greatly overestimated.

  • What's stopping you? Get the money and launch yer ass into orbit.

    The role of government in space should be ZILCH. If you think otherwise, look at its fucking track record.

    You mean the track record that put us on the moon THIRTY YEARS AGO when most countries were happy to have running water? Oh yeah, I'm sure we would've landed on the moon if it was left to companies who have to keep Wall St. happy on a quarterly basis.

    If the government hadn't had its hands in there we would have been on the moon five years earlier.

    If you turn off Rush Limbaugh for a few minutes and check your history books or talk to some of the people involved you'll quickly see that statement is ridiculous. I followed the space program quite closely in the sixties, and we were lucky any of that stuff worked. Who do you think does the work? Private contractors. If they could have done it faster, commercially, and made money at it they would have. They didn't.

  • It is only "open source" if you define "open source" as "done by enthousiasts in their spare time". I don't think the "open source" folks will accept that definition... While some design information, like block diagrams, is available in various scattered papers submitted to amateur satellite conferences, there is no complete documentation available to the world. No circuit diagrams, technical drawings, let alone sourcecode of the software running on the IHUs (the onboard computers). Some people already indicated it would have been good if that was the case (because of peer review possibility). The reason for not doing it seems to primarily the extra work it would be for the core design, construction & control team to document everything well enough to put it on a website. (probably this could be solved by finding a volunteer who can do most of this task without too much involvement from heavily burdened people)
  • I have had my FT-290R and FT-790R (allmode portables, not really handhelds but about the size of the FT-817) since the early eighties. I think they have been available since about 1982. Before that, the IC-202 and IC-402 SSB-only portables existed. About handhelds: when I visited Japan in 1983 I saw a 2 meter SSB handheld of the typical size at that time, i.e. not a carry-on type.
  • Actually, not even ESA is involved in this. Ok, they are involved in the design of the rocket, but not in the launch. Ariane launches are sold and managed by Arianespace (http://www.arianespace.com/), a commercial company.
  • and let responsible corporate entities do what they do best

    What would that be, gouge their customers and dump toxic waste in the local waterway?

    "responsible corporate entities" is a bit like military intelligence - they both DO exist, but only in very small quantities.

    Oh yeah, I'd feel much better if Microsoft was running the space program. No slip-ups, cover-ups or nefarious business practices there. No suh.
  • If you're a developer like me, you definitely realize the technical challenge of developing hardware and software for which you cannot explore all test cases, and cannot test under the real conditions at all, until the thing is sent off in space and you cannot do much about it if something important breaks.

    There is a lot to learn from such a project, about software/hardware fault tolerance. Is there anybody from the project reading this (Bruce, do you know who to contact ?) who could give a basic explanation of the produces involved?

    I know about error-correction for RAM, watchdog timers, duplicate hardware, and self-contained communication code that you can use to get control back. This is pretty classical stuff for the domain I work in (embedded systems); but this is way more impressive.

    I'd love to have someone from the project give a rundown of their procedures, even if not all goes as expected - we can learn a lot from it.

    --
    Emmanuel
  • Sounds like they've had a bad case of "If something can go wrong, it will." Anyhow, the writeup states"...its RAM corrupted every 1 or 2 days in orbit as it crosses radiation belts..." This made me curious as to the major storage medium being used in space? If RAM can be so easily corrupted, it seems that most electronic storage would be just as problematic a storage medium. Do harddrives and/or CDROM storage have this same problem? Is heavy shielding a solution for this? Just curious.

    Penguins have lots of non-volatile RAM. The Linux Pimp [thelinuxpimp.com]

  • Telemetry (Score:1)

    by Anonymous Coward
    I work for a telemetry company as a programmer (www.veridiansystems.com), and I can tell you our bit syncs will lock on just about any signal. I'm not sure what these people are using, I pretty sure it's not our stuff, but with the current state of technology in telemetry, I can say that satelite is as good as dead.

    In another somewhat unrelated note, our company has been in the process of porting some of our "Front End processing" technology to Linux. This is where the real telemetry number chrunching goes on. We are looking to replace Origin 2000 servers with little x86 boxes....
  • actually, read the article and check the link out. the satellite was built by amsat and launched on an ESA rocket. nothing to do with NASA. wake up.
  • So this is kind of an open source satellite, isn't it? At least it is clearly an effort of multiple people donating their own time to a project. And here is a result - a piece of crap in space, useless and broken.

    Next time you try to point fingers at NASA look this up and shut up.
  • Um, this bird was NOT designed, nor built, by NASA. It was designed and built by a corporation, of radio amateurs from all over the world. They had the idea, they raised the money, they built it, tested it, and paid to launch it.

    Don't pin this one on NASA. The hams decided they didn't really need rad-hardened hardware and multiple redundancies. They're learning the hard way, I fear :(
  • It is common for subsystems to fail on satellites. That is why they usually have redundant systems for critical functions. On scientific satellites, there may be many experiment packages on the satellite. You normally don't hear about one of them failing, unless you have an interest in that experiment and read the status reports.
  • NASA has launched lots of duds. You learn this by doing that. This is the 40th Amateur satellite to reach orbit, and while it's the most ambitious, these folks know what they are doing.

    Thanks

    Bruce

  • A backup flight computer without a watchdog timer? Couldn't they rip out out of a Pac-Man machine and use it?

  • Not the best link, but there are a couple of nice tutorials here.

    http://rk.gsfc.nasa.gov/
  • You can't receive it if it's not sending. One of the ground controllers has deep experience in writing software modems and did in fact design the RF link-layer used for much of digital Amateur radio. For the hams in the audience, this is G3RUH. Actually, if this particular beacon was sending properly I could get it, and decode it, at home with no problem.

    Thanks

    Bruce

  • Re:Why they are experimenting with CPUs (Score:3)

    by Flavio ( 12072 ) on Friday December 22, 2000 @03:27PM (#542788)
    The rad-hard CPU of choice for spaceborne equipment is the 1802. Remember the RCA COSMAC personal computer of long ago? I think they have this in silicon-on-sapphire. There are a small number of satellite hackers who still practice 1802 assembler at this late date. It should suffice to say that nobody uses this CPU for anything else any longer. So, an experiment with a modern CPU was very desirable. It looks like the problem might not be in the CPU.

    Well, unfortunately I don't remember the RCA COSMAC PC because I wasn't even alive back then :)

    I do remember that this exact same CPU is one exotic baby, starting with its silicon-on-sapphire CMOS fabrication. It's in the heart of the Viking, Voyager and Galileo!

    As I couldn't remember anything else, I had to consult the "Great Microprocessors of the past and present" page.

    Here's the text for those who actually don't wanna visit the page:

    RCA 1802, weirdness at its best (1974)

    The RCA 1802 was an odd beast, extremely simple and fabricated in CMOS, which allowed it to run at 6.4 MHz (at 10V, but very fast for 1974) or suspended with the clock stopped. It was an 8 bit processor, with 16 bit addressing, but the major features were it's extreme simplicity, and the flexibility of it's large register set. Simplicity was the primary design goal, and in that sense it was one of the first RISC chips.

    It had sixteen 16-bit registers, which could be accessed as thirty-two 8 bit registers, and an accumulator D used for arithmetic and memory access - memory to D, then D to registers, and vice versa, using one 16-bit register as an address. This led to one person describing the 1802 as having 32 bytes of RAM and 65535 I/O ports. A 4-bit control register P selected any one general register as the program counter, while control registers X and N selected registers for I/O Index, and the operand for current instruction. All instructions were 8 bits - a 4-bit op code (total of 16 operations) and 4-bit operand register stored in N.

    There was no real conditional branching (there were conditional skips which could implement it, though), no subroutine support, and no actual stack, but clever use of the register set allowed these to be implemented - for example, changing P to another register allowed jump to a subroutine. Similarly, on an interrupt P and X were saved, then R1 and R2 were selected for P and X until an RTI restored them.

    A later version, the 1805, was enhanced, adding several Forth language primitives. Forth was commonly used in control applications.

    Apart from the COSMAC microcomputer kit, the 1802 saw action in some video games from RCA and Radio Shack, and the chip is the heart of the Voyager, Viking and Galileo (along with some AMD 29000 bit slice processors) probes. One reason for this is that a version of the 1802 used silicon on sapphire (SOS) technology, which leads to radiation and static resistance, ideal for space operation.

    Thanks for the info, Bruce!

    Flavio
  • I got into ham radio as an "alternate" hobby to
    get *away* from computers for a while. After
    intending to take the test for no-code Technician
    for the past 2-3 years, I finally took and passed
    it about 3 months ago.

    I like knowing that the Internet may go down, but
    I'll still be able to get in touch with people in
    the nearby area via the 5 watt HT I carry in my
    truck, or the 5-to-50watt mobile rig I have setup
    as a base station at the house. My equipment is
    no fancier than a good length of antenna
    feedline, and a simple mag-mount (meant for
    mobile use) 5/8-wave 2-meter antenna stuck to the
    top of my window AC unit. Simple, but effective.
    Also, even though its slow, 1200 baud packet
    radio is a LOT of fun.

    Bill (KD5LQR)
  • Argh. I probably made a typo and Slashdot ate my link. Here it goes:

    Great Microprocessors of the Past and Present (V 12.0.0) [sympatico.ca]

    The RCA 1802's in there.

    Flavio
  • Sigh. I don't know about you, but this really un-made my day. AMSAT has to be about the bravest amateur experimenter group out there. They envisioned a new day for ham radio powered by a super satellite that would give you worldwide range with a walkie-talkie and a handheld beam. We have that now to some extent, but not as reliably and not for as many people as they were planning. Well, they aren't quitters, and if this bird turns out to be a loss (not necessarily the case yet) we'll see the same capability in a series of smaller, cheaper, easier-to-launch birds.

    We did have some good news for hams this week - the space station ham rig is running great, and Germany just lowered the Morse Code requirement to an easy 5 words-per-minute like the U.S. Now, we just have to get rid of that code requirement entirely.

    Thanks

    Bruce

  • Whoever just moderated this comment down to a zero, you are EXACTLY the type of idiot I'm talking about.
  • AMSAT-OSCAR 40 Status report of December 13, 2000 Nearly four weeks have now passed since the launch, and there are some good things and some bad things to report. As you all know, immediately after separation, we could not receive the 70 cm transmitter. Consequently we programmed IHU-2 to act as repeater and use the 2m middle beacon instead as our main downlink. In addition the two S-band transmitters have been operated occasionally, but the geometry within the orbit must be right to have the antennas point into the general direction of earth. This limits the use we can make of S-band. The main activity so far for the command stations was to learn to fly the s/c and to prepare it for the first burn with the 400 N motor. This required a reorientation - the s/c must point opposite to the perigee orbital speed vector - and a spin-up to about 9 rpm. In view of this ongoing work, it was decided to postpone the analysis of the problem with the 70cm Tx to a time after the first burn. The reorientation of the spacecraft turned out to be more time-consuming than initially assumed. We had two problems to solve: 1. As we get to our firing attitude, the geometry is very poor for producing direction changes of the spin-vector. The magnetic field of the earth is nearly perpendicular to the spin axis meaning that we can change rpm easily, but not direction. It turned out that rounding errors in the software of the IHU were in the same order of magnitude as the desired spin-change. Thus reliable control was not possible. But careful tweaking of the parameters used in the IHU finally enabled us to solve this problem. 2. The geometry is also poor in terms of attitude determination by our sensors with earth and sun viewed almost from the same direction. In fact for a certain time the earth sensor was blinded by the sun and delivered no useful data at all. But here the YACE camera in conjunction with the IHU-2 came in very handy. By taking pictures of the earth at strategic times we could use the YACE as another earth-sensor looking to the top of the s/c. It gave us badly needed additional data. The IHU-2 played a vital role in processing and storing these pictures. Unfortunately the IHU-2 turned out not to be so reliable as the IHU-1; every one or two days it crashes. This results in the beacon transmitting only a weak carrier, but no modulation, until the IHU-2 is manually reset from the ground. So far this posed no real problem, but it is a nuisance. Also we have now some data of how the memory is corrupted by radiation. Eventually we hope to install additional software in the IHU-2 which allows us to avoid or at least automatically recover from these crashes. But this has to wait until things get a bit quieter. Until this time we will have to live with the IHU-2 crashes, which seem to be caused by hard radiation and typically occur, when the s/c comes out of perigee and enters the radiation belts again. Around Sunday Dec. 10 we had finally reached the proper orientation and spin for the first 400 N motor burn to take us to 50000 km apogee altitude. After reviewing the various constraints it was decided to execute this burn on Monday, Dec. 11 in the perigee of orbit 50/51. The necessary program was uploaded - this is an automatic sequence since the s/c is at this time at the equator with only 600 km altitude. Thus no command stations can be in contact with the satellite at the time of the burn. So perigee 50/51 came and went - but the burn did not take place. The stored telemetry was analysed and it was found that the sequencer went through all the necessary steps, but no helium pressure was built up and consequently the burn did not take place. (It takes helium pressure to open the fuel-valves.) On Monday Dec. 11 the situation was investigated and it was found that the pressurisation command was not resulting in any action. Initially the investigation concentrated on a software discrepancy, which existed between the software to test the system in Kourou and the one used in flight. But it was found that this probably was not the cause - the valve(s) simply refused to open. We had such a problem before during the test phase of the s/c, and one of the helium valves was repaired as a consequence. All the indications are that we ran again into this type of problem - which may be caused by the age of the components we are using. We then executed multiple open and close commands, which eventually got the helium flowing. But it was also noted that the helium flow was almost an order of magnitude less than required. Still we build up pressure in the tank to nominal and then programmed the s/c to perform the burn on Monday evening. This time the burn started properly, but there were some anomalies in the telemetry indicating that the burn did not stop at the programmed time but lasted about 3 minutes longer. Thus we achieve an orbit with about 60,000 km apogee altitude. For our ultimate plans this is no problem, we would have used the electric propulsion anyway to further increase the apogee. James Miller had written a data collection program for IHU-2, thus we have a very detailed account of all the events of this burn. A detailed analysis is under way, but we have already some first indications of the nature of the problem and also possible ways to cure it or at least to cope with it, provided that the motor was not damaged by this event. During the next days we will investigate this matter in detail. If we have a real problem with the 400 N propulsion system, we may need to change our strategy for achieving a useful final orbit. But it may also mean only that we have to observe a number of boundary conditions during the following burns and that the situation may have no impact on the mission goals. For the next days no attitude changes are planned, thus we will be able to start to investigate the problem with the 70cm TX. During these tests we will find out if we can operationally plan on using the 70cm TX or not. So we are living exiting times. Finally we would like to express our compliments and our appreciation to the command stations for the superb job they are doing. Each day they are facing new difficulties requiring a very large amount of time and dedication. They are doing a SUPER job
  • I'm not stupid, I'm disabled. Get it straight.
  • I read at -1 and see everyone's posts. If not many non-bruce posts are displayed, it's because you've set your threshold too high. If you are seeing them without parent posts (except for the update post) it's because the answers were moderated higher than the questions.

    Until we got a few other hams posting there were few people here who had any information on the topic, and I answered all sensible questions, as I'll usually do on my own articles. I hardly think this is improper.

    Thanks

    Bruce

  • I was wondering if anyone would take me to task for not considering the Wilderness Radio and Norcal stuff to be handhelds.

    Oh, I suppose you can classify that 1962 Tuna Tin radio as a handheld, too :-) No doubt there is military stuff from the Korean war era, as well.

    Thanks

    Bruce

  • Their web site is amsat.org . If you want to learn about what they are doing, go to arrl.org and buy the "Satellite Anthology". I think ARRL or AMSAT have some conference proceedings available, as well.

    If you want to talk with an AMSAT developer directly, try Bdale Garbee bdale@debian.org . He did the GPS experiment and possibly some other stuff, and was part of the pre-launch prep team in Ghana.

    Thanks

    Bruce



  • That is an amazingly high number of failures for something like this.

    I always percieved space vehicles to be perfect and assumed that nothing every broke on them, but simply wore out by design

    Is is normal to have so many things fail on a space vehicle? Does this kind of thing always happen, but doesn't get mentioned?

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