Actually, the modem does deal gracefully with bit errors. It protects the most important bits and lets the less important ones get clobbered. In a high bit error situation you get speech that sounds wrong but can still be understood. FEC actually falls down sooner than this scheme.
Being at Pixar, being Debian project leader, my technical work on Debian, and announcing Open Source. Those things interested a lot of people. And founding No-Code International stirred up a lot of controversy in the radio amateur world.
There are commercial codecs that get to slightly lower data rates, which the government presently uses.
I once had to ask the Pakistani military to not use the mailing list to ask questions, as I didn't want our ham radio project to get in ITAR trouble. Of course they can still use the code, it's Open Source. But they have to get help elsewhere.
That's the theory. The modem also degrades gracefully in a way that lets you use your "ears" to recover information when there are bit errors. No on-off behavior like most digital codecs, in fact one of the samples is rendered with 1% bit errors, which might kill a normal codec or at least require a packet repeat. We have higher bit rate versions of the codec that don't make you work so hard.
I recruited David to work on this because I felt that Amateur Radio operators should not be bound to any locked-down technology but should be able to tinker with all of their technology. At the same time, there is a similar controversy regarding closed codecs on the Internet.
I've been programming all day, and haven't said many words at all. There are people who talk for their entire work day, but they generally spend half their time listening and more processing something, so they may actually do 4 hours of speech or less in the work day. Most people don't really speak for more than a few hours per day.
Actually, our modems degrade gracefully. The least-protected bits go wrong with low bit-error rates, and the more protected bits survive. It takes a high bit error rate to kill it. So bit errors result in the speech being "off" but not dropping out.
The only question would probably be whether we had allocated enough bits for pitch and collected it over a small enough interval.. Pitch is definitely encoded.
There really are downloads but you don't do them. The main page, opened normally from the browser, links to a cache manifest file. Everything listed in that file is downloaded and long term cached by the browser. From then on you have the app in local storage. If you save the front page to the desktop, it gets an app icon and opens full screen in an undecorated browser (no URL bar, etc.) and looks just like any other app.
They have enough polar-orbit launches on the manifest that every two weeks means once per month per coast. Polar at Vandenberg, equatorial at Canaveral.
Actually, all of the ground landings take place right next to the ocean. The rocket doesn't vector over the land until it's close to the ground, and the landing pad has lots of buffer zone around it.
Consider the financial impact, too. A successful landing is saving 35 Million dollars.
Falcon 9 (the non-heavy one) is about to go to its 5th major revision, and there have been major increments to its capability with each one. So, it will probably just take time for a version of F9H to have crossfeed and some additional delta-V. It was possible to get F9H going without the added complexity, so they did.
How does this affect anyone's life at all?... 'm sure I'll be censored to -1 by moderators who prefer to dodge the important questions.
It's not that anyone is dodging an important question. It's that the question is, I'm sorry, naive. The benefits of space research are around you every moment of your life.
The Apollo program, for example, used some of the first integrated circuits. This work progressed to essentially all modern electronic devices.
All of Musk's businesses lose money every year. Where exactly do they get the funds for all this expansion, or for the Gigafactory or the Tesla 3 tooling and production?
Maybe your news sources are not reliable. Musk's previous business efforts have made a ton of profit and he has reinvested his own funds in his more recent efforts. Tesla is a public stock company, so both institutions and individuals are invested in it. SpaceX is privately funded, you can see who the investors are here.
Not one single Falcon has landed without mayor damage today.
Actually, I'm not sure of that. My impression was that the Space Station delivery boosters which go to landing-zone 1 at Canaveral end up in pretty good shape, and some of the ones that land on the barge as well.
The ones that got lots of damage were rockets with so little fuel left from their missions that they had to skip one or two of what otherwise would be re-entry burns. These came down very fast and had frictional heating damage, among other things.
If that rocket lands on its own, within only a few feet of where it's intended to go, having come back from space (and close to orbital space), you really have to assume that everything is working until that moment.
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You are leaving out that it encoded the pitch separately, and a voiced/unvoiced bit.
Actually, the modem does deal gracefully with bit errors. It protects the most important bits and lets the less important ones get clobbered. In a high bit error situation you get speech that sounds wrong but can still be understood. FEC actually falls down sooner than this scheme.
Yes, but it's hardly continuous and, going by my kid when he was younger, rarely makes any sense.
Being at Pixar, being Debian project leader, my technical work on Debian, and announcing Open Source. Those things interested a lot of people. And founding No-Code International stirred up a lot of controversy in the radio amateur world.
There are commercial codecs that get to slightly lower data rates, which the government presently uses.
I once had to ask the Pakistani military to not use the mailing list to ask questions, as I didn't want our ham radio project to get in ITAR trouble. Of course they can still use the code, it's Open Source. But they have to get help elsewhere.
That's the theory. The modem also degrades gracefully in a way that lets you use your "ears" to recover information when there are bit errors. No on-off behavior like most digital codecs, in fact one of the samples is rendered with 1% bit errors, which might kill a normal codec or at least require a packet repeat. We have higher bit rate versions of the codec that don't make you work so hard.
It's free software, not for sale.
I recruited David to work on this because I felt that Amateur Radio operators should not be bound to any locked-down technology but should be able to tinker with all of their technology. At the same time, there is a similar controversy regarding closed codecs on the Internet.
I've been programming all day, and haven't said many words at all. There are people who talk for their entire work day, but they generally spend half their time listening and more processing something, so they may actually do 4 hours of speech or less in the work day. Most people don't really speak for more than a few hours per day.
You don't record the pauses. You do sleep, you know :-)
Actually, our modems degrade gracefully. The least-protected bits go wrong with low bit-error rates, and the more protected bits survive. It takes a high bit error rate to kill it. So bit errors result in the speech being "off" but not dropping out.
The only question would probably be whether we had allocated enough bits for pitch and collected it over a small enough interval.. Pitch is definitely encoded.
You can try it pretty easily, if you speak such a language. There are test programs that work on sound files.
Almost all F9H missions will land the center booster on a barge. It gets too far downrange to return to the takeoff point.
Saturn V had one too. There was a range safety officer with a button that would kill three people if he pushed it.
If they advertise a full-thrust mission capability, someone will make something to use it.
There really are downloads but you don't do them. The main page, opened normally from the browser, links to a cache manifest file. Everything listed in that file is downloaded and long term cached by the browser. From then on you have the app in local storage. If you save the front page to the desktop, it gets an app icon and opens full screen in an undecorated browser (no URL bar, etc.) and looks just like any other app.
They have enough polar-orbit launches on the manifest that every two weeks means once per month per coast. Polar at Vandenberg, equatorial at Canaveral.
Actually, all of the ground landings take place right next to the ocean. The rocket doesn't vector over the land until it's close to the ground, and the landing pad has lots of buffer zone around it.
Consider the financial impact, too. A successful landing is saving 35 Million dollars.
Falcon 9 (the non-heavy one) is about to go to its 5th major revision, and there have been major increments to its capability with each one. So, it will probably just take time for a version of F9H to have crossfeed and some additional delta-V. It was possible to get F9H going without the added complexity, so they did.
It's not that anyone is dodging an important question. It's that the question is, I'm sorry, naive. The benefits of space research are around you every moment of your life.
The Apollo program, for example, used some of the first integrated circuits. This work progressed to essentially all modern electronic devices.
Maybe your news sources are not reliable. Musk's previous business efforts have made a ton of profit and he has reinvested his own funds in his more recent efforts. Tesla is a public stock company, so both institutions and individuals are invested in it. SpaceX is privately funded, you can see who the investors are here.
Crossfeed is not planned for F9H in the near term. They may get to it eventually.
Actually, I'm not sure of that. My impression was that the Space Station delivery boosters which go to landing-zone 1 at Canaveral end up in pretty good shape, and some of the ones that land on the barge as well.
The ones that got lots of damage were rockets with so little fuel left from their missions that they had to skip one or two of what otherwise would be re-entry burns. These came down very fast and had frictional heating damage, among other things.
If that rocket lands on its own, within only a few feet of where it's intended to go, having come back from space (and close to orbital space), you really have to assume that everything is working until that moment.
If you want to view the launch live, instructions are here.