Report from Hamvention

Technocrat

Report from Hamvention

Bruce Perens

Mon May 19 18:08:00 -0700 2008

Amateur+Radio.

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So, Hamvention is over for the year. My own news items are:

The Codec2 project is now an AMSAT project. Rocket scientists 'r us.
ARRL's 5th pillar.

Hamvention was poorly attended. My guess is about 14K people, down 5K or more from last year. I guess nobody wanted to spend that much on gas, if they had the money at all. There were swathes of empty parking spots in the flea market. They lost enough indoor exhibitors to dedicate one of the previous indoor booth rooms to be a forum room. What was left seemed busy enough.

I discussed the Codec2 project with AMSAT's president. I'd previously presented on the idea at their technical conference, and at the TAPR/ARRL Digital Communications Conference. He gave his OK for it to be an AMSAT project. This will help me in getting grants, etc., as everybody likes to be associated with space R&D. There is no committment to use one of our codecs on their next satellite yet, but then we don't have a codec yet.

ARRL announced its 5th Pillar, which means that they will expand the PR campaign for Amateur Radio to emphasize technology, along with the previous four pillars: Public Service, Advocacy, Education and Membership. What this means to us is that they have a technology committee again. I did my best to get involved with that committee.

One of the ARRL directors brought over one of the people behind Winlink 2000 to talk about its less-than-wide-open status. The Winlink folks say they are using stock IETF protocols over a $1000 proprietary Pactor card. They want us (mostly meaning TAPR) to provide an open solution to replace that. I discussed how to do that with Phil Karn KA9Q and others. There are potentially regulatory hurdles, depending on how we go about that.

The Fifth Pillar of the ARRL

AB3A

Tue May 20 04:06:19 -0700 2008
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I think the ARRL has it just right. Ham Radio has to morph in to something slightly better than just an anachronistic way for radio enthusiasts to communicate.

We should be experimenting with CODECs. We should be recruiting people to try playing with some of this "wireless" thingie. But we can't sit on our laurels and expect them to come to us.

The ARRL needs to evangelize on the Internet. Ham Radio used to be the internet of our parents generation. Technical people frequently met on the air to discuss all sorts of interesting things. Now they get better communications on the Internet. So why bother with radio?

People are also getting used to radio as a brick that "just works." They don't realize there are some actual limits to the performance of these devices. Pushing those limits seems to be one of those notions that very few people want to play with in their free time any more.

That's one reason why I think AMSAT-DL's Phase 5 (interplanetary) spacecraft would inspire a lot of people to get interested in radio again.

Dayton's Shrinkage comes as no surprise. The way most people are interested in this hobby offers very few things to the younger crowd. We need something to capture imaginations. The fifth pillar should be a start. CODEC experimentation would be an interesting interlude. But for long term interest, look toward space...

The Fifth Pillar of the ARRL

Harry the Bastard

Tue May 20 19:13:13 -0700 2008
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I worked on a project approx 15 years ago that produced "acceptable" performance at 2400 (using a CELP codec). Don't know how it performed once the bit error rate started to become an issue. It does surprise me somewhat that the MELP patents have not yet expired, or that some hams have not yet cobbled together something that essentially avoids the major patents.

Speech coding has been a research subject for a considerable amount of time now. The phsyco-acoustic models that are used in decomposition of human speech to digital data probably go back 30 or more years, so it surpises me that any (valid) patents have been granted in the last 15..20 years. Analog Devices had a fairly good description of a LP codec which they published in a ADSP2100 book that must be at least 15 years old! (Don't know how well their implementation worked though ...)

(from one of the links) I am curious about the radiation requirements for space born equipment ... The CDP1802 is ancient, its major features were that it only required flea power to run, and that it was inherently radiation proof. (I am sure the ones flown on sats are even more hardened) However, the COSMAC is by no means fast enough to do the relevent DSP required for even a simple voice CODEC. I would have thought that modern Amateur sats would be using FPGA's anyway. There are several vendors offering radiation hardened FPGA's, and this means that even the micro itself can be reconfigured on the fly. a high gate count FPGA could easily do the micro, DSP, etc functions required and yet still have lots of unused gates for future enhancements. (Also means that should some part of the FPGA become permanently damged, a work around could still be uploaded to the FPGA that just routed around the damaged cells)

... I am sure people smarter than I have already put forth similar arguments ...