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Comment: Re:Legitimate use for 3D printing (Score 1) 56

by smellsofbikes (#49147919) Attached to: Researchers Create World's First 3D-Printed Jet Engines

Jet engines are an awful candidate. The tolerances and material requirements to not tear themselves apart are tremendous. We're talking about turbine blades spinning at 5k-45k RPM, at temperatures of several hundred degrees, and pressures far above atmospheric, and an airstream a few hundred MPH in velocity.

The inspection process for the individual blades, and then then for their attachment to the mount, to ensure that an imbalance doesn't destroy the engine is tremendously demanding.

On the other hand, there is a case to be made for an aim-for-the-stars strategy. If you can build a turbine blade you can build anything. I would have thought compressor blades would be a much more likely candidate, but if they can get this to work, more power to them. And maybe 3d printing will give them options they would not otherwise have: internal bleed air cooling channels that follow the leading edge along its curvature, for instance. It's possible that given completely different design and manufacturing capabilities, they'll be able to make something that can do the same job with different tradeoffs.

Comment: Re:Just y'know... reconnect them spinal nerves (Score 1, Flamebait) 208

by NotBornYesterday (#49146787) Attached to: Surgeon: First Human Head Transplant May Be Just Two Years Away
Morally speaking, testing on lawyers and politicians would be preferable to using rats. However, scientific consensus is that the lack of a high-functioning nervous system in most politicians and lobbyists, et al, means that any results would not likely work on real humans.

Comment: Re:GNUradio? (Score 1) 131

Test equipment is allowed to transmit and receive on those frequencies. If it looks like a radio, it can't. I have a number of cellular testers hanging around here that can act like base stations, mostly because I buy them used as spectrum analyzers and never use the (obsolete) cellular facilities. Government has different rules regarding what it can and can't do in the name of law enforcement, although FCC has been very reluctant to allow them to use cellular jammers.

If you can afford it, something from Ettus would better suit your application.

Comment: Re: Fuck it - everyone for themselves. (Score 1) 360

by WindBourne (#49141927) Attached to: The Groups Behind Making Distributed Solar Power Harder To Adopt
The reason why America comes up with such high per capita is because we have such high GDP output, which is where our energy goes into.

The trade imbalance with China is because CHina manipulates their money illegally, along with dumps. What happens if they free their money the way that they were supposed to back in 2005? Well, it would overnight stop the imports.

Greed? You think that America is any more greedy than any other nation or their top ppl? Give me a fucking break. Our top 1% is just as greedy as your top 1%. The real difference is that our top 1% does not have regulations on them to keep the work at home. Nor do they have a gov that helps them keep it at home by manipulating money as well as massive subsidies for them to dump on other nations.

And being the largest consumer of resources? Not even close. Hell, CHina now burns 1/2 of all coal on this planet. They import and burn far more than America does.

It gets old when ppl make up BS about others with nothing to back it up.

And yeah, I think that you know that.

Comment: Re:"Proprietary So I Get Paid", from Bruce Perens? (Score 1) 131

Hi AC,

Matt Ettus has a story about a Chinese cloner of the USRP. The guy tells Chinese customers that it is illegal for them to buy from Ettus, they must buy from the cloner instead. Then, when they have problems and require serivce, he tells them to get it from Ettus. Who of course made nothing from their device sales and can not afford to service them.

This is not following the rules of Open anything. It's counterfeiting.

So, sometimes it is necessary to change the license a little so that you will not be a chump. I discussed the fact that the hardware is fully disclosed but not Open Hardware licensed with RMS, the software is 100% Free Software, and there is a regulatory chip you can't write. We can go for Respects Your Freedom certification that way..

I've paid my dues as far as "Open" is concerned, and Chris has too. This is all we can give you this time.

Comment: Re:Why custom punched end panels ? (Score 1) 131

The case selection was so that we'd have at least one case that would work. We did not take much time on it. We'd be happy to have other people designing and selling cases.

The version after this one requires cases that look like real radios. That is going to be a bigger problem. We don't yet have a mold-design partner, etc.

Comment: Re:GNUradio? (Score 2) 131

We implement it as a chip that intercepts the serial bus to the VFO chip, and disallows certain frequencies. On FCC-certified equipment we might have to make that chip and the VFO chip physically difficult to get at by potting them or something. This first unit is test-equipment and does not have the limitation.

Comment: Re:How about international versions? (Score 1) 131

Anyone who is good at electronics can get around regulatory lockouts. We're not allowed to make it easy. But nor are we technically able to make it impossible.

U.S. regulation only allows Part 95 certified radios to be used on GMRS, and Part 95 requires that the radio be pretty well locked down. But all of those Asian imports are certified for Part 90 and there are lots of users putting them on both Amateur and GMRS. If FCC wanted to push the issue with any particular licensee, they could.

Comment: Re:awesome! (Score 1) 131

The D-STAR issue is not really ICOM's fault. JARL designed D-STAR (not ICOM) and put the AMBE codec in it because nobody believed that you could have a good open codec at the time. We now have Codec2 (a project I evangelized and recruited the developer) which is fully open. And we do have a software AMBE decoder in Open Source, although the patents won't let us use it. That is why I am working on the patent issue (as noted in the last slide of the presentation).

I know about the counterfeit FTDI chips, and Matt Ettus told me what has happened with the Chinese clone of USRP. We know what to do.

Comment: Re:Many are leaving ham radio too (Score 1) 131

And it's because of No-Code. We looked at the licensing statistics and thought we'd preside over the end of Amateur Radio in our own lifetimes. That's the main reason I worked on no-code. There was really strong opposition among the old contingent, and ARRL fought to preserve the code for as long as they could. Someone even asked me to let Amateur Radio die with dignity rather than sully it with no-code hams. Gee, I am glad that fight is over.

Comment: Re: Many are leaving ham radio too (Score 1) 131

Though a nice compromise might be to allow such things in certain bands only.

That is why there are different radio services. Hams really only have a few corners here and there of the radio spectrum. There really is a service for everyone, although you should be aware that the entire HF spectrum would fit in a few WiFi channels, and all of the Amateur HF spectrum would fit in one. So, we don't really have the bandwidth at all. And people who want the bandwidth on UHF already have WiFi and the various sorts of RF links, etc.

Comment: Re:Many are leaving ham radio too (Score 1) 131

The internet really sucks and we don't want another one on ham radio. Nor could we possibly have the bandwidth to support one. The entire HF spectrum fits in just a few WiFi channels.

To satisfy the demands of the "it should be anything goes" crowd, we have CB radio. And there are all of the common carriers, etc.

So, I can't sympathize, and even if I did, there are not the technical resources there.

Sorry.

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