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Comment Not actually batteryless (Score 4, Informative) 110

Apparently it uses 1.5mW at 1V.

You can get batteryless radios. Crystal radios (which don't necessarily contain a crystal) get all their power from the radio signal, and they're scarily simple. During the second world war foxhole radios were built out of a razor blade, a pencil, some wire and a set of headphones (instructions: http://www.bizarrelabs.com/fox...) Prisoner of war radios used coal

AFAIK, however, the much lower energy VHF signals for FM isn't capable of running an FM decoder, and probably not an earpiece either.

I wonder if a modern crystal earpiece could usefully pick up low-power AM transmissions from a cellphone in your pocket without spamming everyone around you with radio waves?

Comment Re:GNUradio? (Score 1) 135

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:Good method for improving (Score 1) 347

If you don't have it, you'll make bad decisions. For example, answer the question, "should I use framework A, or should I write some code myself?" If you can't estimate how long it will take to use the framework and compare it to how long it will take to write the code yourself, then it is impossible to make a realistic decision.

That's a bad example because that's almost never my criteria. I could write my own framework almost as quickly as I could suss out the quirks of someone else's, and that's usually a teensy part of the overall project lifetime anyway. Instead, I judge on things like "do I want to spend the rest of my time here maintaining this thing?" and "who's going to own security updates?" and "will it be easier to hire people with experience on this one or on the one I haven't written yet?". Sometimes there's no good framework A to use, or maybe framework A exists and is popular but is unfit for this specific purpose, so we write something in-house. Either way, notice that "time to get started" is a trivial or nonexistent part of the equation.

Comment Re:"Proprietary So I Get Paid", from Bruce Perens? (Score 1) 135

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) 135

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) 135

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) 135

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) 135

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) 135

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) 135

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.

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