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Comment Re:Morse Code (Score 2) 620

Yes, I know about the NAVAIDs, but they identify at 5 WPM and the airman's charts print the dots and dashes next to the waypoint. And there might still be runway aids that say a few letters, also at 5 WPM, but it's always the same letters for left and right and the outer, middle, and inner marker. Pilots learn the sounds for each.

When I was a Technician licensee, all of the repeaters were populated mostly by Technician licensees, and identified much faster than any of them could copy. So it was clear the Morse tone (erroneously called a "CW" ID because it wasn't Constant Wave) was there for a legal requirement only. But most of the repeaters could identify in phone, too. Back in NY, we had WR2ACD identify with the voice of the famous CBS news anchor Walter Cronkite, who was of course KB2GSD.

Comment Re:Morse Code (Score 3, Interesting) 620

The Novice license stopped being the path to entry once the no-code Technician licensing started. There was indeed an ITU requirement, but it was at the behest of IARU, not as the requirement of any government. Similarly, FCC actually raised code speed requirements at the behest of ARRL. Shore stations had moved to phone and teletype decades before. Most ships no longer employed radio operators, but left that duty to other staff who only used phone. There was only a token continuing monitoring of Morse ship transmissions, now entirely gone.

There was one pro-code guy who pleaded with me to allow Amateur Radio to "die with dignity". If nothing else did, that convinced me that the pro-code folks could see the end coming and would accept it as long as it came after they died. Amateur licensing was declining fast, operators were dying faster than new ones got licenses, and we could see the end of Amateur Radio would come in a few decades at most..

Now there are more hams than ever, and Amateur Radio is healthy. When I say "We won", it means "Amateur Radio won". It's too bad we had to fight our own old guys.

There isn't really any reason for government agencies and NGOs to use Amateur Radio. They have satellite phones, etc. But if it really bothers you, why not lobby against allowing compensation for operators? I'd join that bandwagon.

Comment Morse Code (Score 5, Interesting) 620

I lobbied to end the requirement for an examination of the ability to decode Morse code with your ear and brain. Until 2007, the U.S. Federal Government required it before they would license all but the lowest grade of Amateur Radio hobbyists.

As part of my lobbying effort, I successfully passed a test for receiving code at 20 words per minute, and then subsequently refused to use the code on the air. 20 WPM is so fast that you have to decode by the sound of each character, you don't have enough time to pick out the individual dots and dashes.

We won.

Comment Re:Futile search? (Score 1) 208

I agree with most of what you wrote. But I have the most interest in sample returns because we have such vastly greater analysis capabilities here on Earth than we could ever send on a mission - especially a lower budget mission. And by leaving off surface science hardware, you save development costs and a significant amount of spacecraft mass.

Also, capturing samples, you don't have to land to have a low impact velocity. If you reach Saturn via ion propulsion then you could at little cost enter a Molniya-like orbit over the plumes so that the spacecraft would be nearly stationary relative to the particles during collection. Enceladus orbits are slow to begin with due to the low gravity (0,114m/s versus Earth's 9,81), and by positioning a high apogee or near-apogee over the plumes it might even be possible to collect jet material at lower impact velocity than one could from the ground. Enceladus's gravity would contribute to decelerating the particles and, if desired, one could have the probe's ascent phase over the plumes (rather than the apogee) for further relative velocity reduction. Impact velocity would be not much more than the random variation between the particles' individual trajectories, and some would impact with near-zero velocity. Combined with a carbon aerogel collector (much less dense than the silica aerogel used by Stardust), I seriously doubt you'd do any damage at all to what's collected - most particles shouldn't even melt.

Every added system is added mass and development cost; landers don't usually come cheap, even on a low-gravity body like Enceladus. And dropping a lander near potentially unpredictable fissure geysers carries a risk. So I personally tend to favor spaceborne collection. That said, one would probably learn more from the surface, and you'd be able to sample surface ices as well, not just plumes.

Comment It's not just audio triangulation (Score 1) 220

The sound triangulated was in cryogenic liquid oxygen at 50 PSI. The speed of sound in that is approximately 1 kilometer per second.This paper is about calculating the exact speed. Elon talked in the conference about reading telemetry with millisecond accuracy. But this would yield only 1 meter resolution.

Comment Re: Try Stack Overflow and --synclines (Score 1) 91

Roger,

This is great. It does look like a 1:1 mapping to what we expect autoconf to do, except neater and maintainable.

The only problem with selling this to GNU folks is that it would make CMake a prerequisite to everything. But I think it's worth it. And then there's inertia. And the language isn't as pretty as we'd like.

Can you see any other possible objections?

Thanks

Bruce

Comment Re:certified materials (Score 3) 220

You think having the part designed to handle five times the load it actually experienced to not be "with sufficient margin"? How much of a margin do you want them to put, 100x?

RTFA. They were doing statistical-sampling quality control testing of struts. The problem was that most of them were just fine, but there were a very small number which were totally defective and broke at a tiny fraction of their rated value. And no, SpaceX did not make the parts, it was an outside supplier. And yes, SpaceX A) will now be testing 100% of them, and B) is ditching the supplier.

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