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Comment: Re:Viewing Launches (Score 1) 22

by Bruce Perens (#49166815) Attached to: SpaceX Falcon 9 Launches Dual Satellite Mission

With luck, they'll start incorporating our radio transceivers. I hear that SpaceX flies with several USRPs now, so that's not completely unrealistic. That might be as close as I can get. Anyone who can get me a base invitation, though, would be greatly appreciated and I'd be happy to do some entertaining speeches while there. I need a base invite for Vandenberg, too. I got in to the official viewing site for the first try of the last launch (and that scrubbed too), but this next one is on Pad 6.

Comment: Viewing Launches (Score 3, Interesting) 22

by Bruce Perens (#49164783) Attached to: SpaceX Falcon 9 Launches Dual Satellite Mission

I was in Florida to speak at Orlando Hamcation and went to see the DISCOVR launch at Kennedy Space Center. I paid $50 to be at LC-39 for the launch, an observation tower made from a disused gantry on the Nasa Causeway between the pads and the Vehicle Assembly Building. A crawler was parked next door! A hot sandwich buffet, chips, and sodas were served. It was cold and windy! I watched for a few hours and unfortunately the launch scrubbed due to high stratospheric winds.

The next day, Delaware North Corporation, which operates tourism at KSC, decided not to open LC-39 or the Saturn 5 center for the launch. This was the third launch attempt and I guess they decided most people had left. I was annoyed.

The closest beach was going to be closed in the evening, it's a sensitive ecological area. I ended up seeing the launch from Jetty Park. This turned out not to be such a great location, the tower wasn't visible at all and the first 10 seconds of the rocket in flight were obscured before we saw it over a hill.

What's a better viewing location?

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:"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.

Comment: Cryptographic keys (Score 1) 131

I am afraid that's not the way it works. Public-key encryption doesn't really give you the capability to decode the communication of two other parties unless you get the secret (rather than public) key, which they have no reason to give you. There is also a session key that is randomly generated and lives only for the duration of the connection, and there is the potential for VPNs or tunneling that further obscure the actual communication. It's actually very difficult for a monitoring station to even get 100% of the packets reliably, although the two stations in the communication do get them. So you may not be able to reconstruct all of the bits in the stream, and this will break decryption too.

All of this adds up to so many technical hurdles that in practice you have to be NSA to decode the communication, hams who are attempting to self-regulate will not have the appropriate resources.

Comment: Re:Bruce, finally something worth while (Score 1) 131

TDMA is time-division multiple access. It just means dividing the channel into time-slots, where each is some number of milliseconds. So, say we had two slots, each 20 ms long. We could receive for 20 ms, and then re-transmit what we received in the next 20 ms. No duplexers, no front-end overload, just one frequency. Works really well with digital modems and voice codecs.

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