Tornadoes and HAMS

Harry the Bastard

Sun Mar 23 20:10:42 -0700 2008

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This is one of the things that "HAM"  radio is good for. It served a vey useful purpose in Australia when cyclone Tracy blew Darwin to bits many years ago!

Unfortunately, I do not see much future for HAM radio. The Internet gratifies most peoples needs RE: inane chatter, etc, so people who wish to become hams in the future will only be a tiny subset of those that in past years actually studied to gain the relevent qualifications.

IMHO this is not neccesarily a bad thing. It might actually be that diehard experimenters will again reign on the ham bands, instead of the multitude that currently have licences, but have no real grasp of the tech that they are using. (It used to be that HAMs made their own equipment ... these days, most HAMs experience comes down to buying commercially made equipment. (Yes, I know, much of that equipment is very nice, but using it takes (almost) no more skill than reheating a meal in a microwave!)

Tornadoes and HAMS

AB3A

Mon Mar 24 04:06:19 -0700 2008

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I've done both. I have built my own gear and I have purchased it. There is still a great deal of technique in setting up a full station.

For example, it does no good to spend thousands of dollars on a fancy high dynamic range transceiver, only to hook it up to a dipole less than 1/4 of a wavelength off of the ground. Building and using a station is not trivial.

Ham radio will continue to be useful in many ways, though the number of enthusiasts seems to be shrinking. First, it's a place for people to experiment and learn about the art of the possible in radio communications. Communications methods such as meteor scatter were discovered by ham radio operators. There will always be a need for a piece of spectrum in which to experiment this way.

Second, Ham radio does not use much infrastructure. A solar powered radio station will continue to function unimpeded for many months after a disaster has wiped out most other communications systems.

Third, people used to use it as a method of social networking before the Internet took hold. Frankly, the internet is better suited for that purpose. While I'll miss the cross section of so many interesting people, I have to admit that the idle chatter won't be missed.

Hams as leading edge? I wish I could believe that...

wowbagger

Mon Mar 24 04:53:55 -0700 2008

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It might actually be that diehard experimenters will again reign on the ham bands, instead of the multitude that currently have licences, but have no real grasp of the tech that they are using. (It used to be that HAMs made their own equipment ... these days, most HAMs experience comes down to buying commercially made equipment.)

Unfortunately, I see the exact opposite happening: the ability to experiment on the bands being squeezed out by regulation upon regulation until the amateur service is nothing but a poorly funded shadow of the commercial portable mobile radio service. Things like D-Star, which has been mandated for all digital amateur radio in Japan (one of the top countries for the amateur radio service), which REQUIRE a proprietary codec (AMBE, by Digital Voice Systems) that CANNOT be implemented by an amateur - you want AMBE, you buy an AMBE codec module from DVSI. Oh, you want to implement your protocol as a module for GNURadio? Tough nuggies - DVSI does not ship a DLL/.SO version of their codec, will not ship such a codec, don't even ask. And if you want to make your own "Free-Star" protocol using Speex - remember that bit about "mandated in Japan"?

Then there are all the regulations about "codes and cyphers" and the regulations on spread spectrum operations - the record keeping requirements make SS very UN-attractive - unless you are just using 802.11 in the amateur segment of 2.4GHz (and we are back to commercial equipment that the average ham cannot build). And if you want to carry health and welfare traffic that shouldn't be discussed over the air, you cannot use encryption of any sort. Now, fold HIPPA regulations into that, and suddenly you cannot tell the emergency operations center what your field medic site needs because you cannot say it over the open air (HIPPA) but cannot encrypt it (part 97).

And what does it take to really do meaningful experimentation? You have to have a background in signal processing, embedded programming, RF design, digital design - if you have that sort of background please contact me with your resumee, as we need to hire you where I work - but if you get a job doing this 8+ hours a day it gets really hard to come home and work on a side project (and I ignore the issue of your place of employment trying to glom on to any work you've done on your own time).

Hams as leading edge? I wish I could believe that...

Harry the Bastard

Mon Mar 24 10:31:26 -0700 2008

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I have not 'played' with Ham radio for a very long time. The last time I re-activated my licence was to 'play' with packet radio. Even then I was aware of limitations that I thought were peculiar. (IE: Maximum bit rates specified for various bands that seemed to have no reasonable explanation. 2400 baud max on 2 meters comes to mind ... This did not seem reasonable to me at the time, and still seems somewhat silly.) 

You are correct in that if you do RF for a job (or electronics in general) the desire to also play with it after hours is extremely low. (in my case, virtually zero, I no longer have any Ham equipment at all, except for a 6 meter portable rotting in a drawer somewhere. IC602)

WRT: AMBE codec. I was not aware that ham equipment existed that even implemented digital voice comms. Unfortunate that the codec is proprietary. There is nothing stoping anyone from generating a reverse engineered implementation from the bitstream, and publishing that on the internet. Patents only affect commercial use. No way could a company sue a HAM using a FOSS version because it can easily be argued that it is NOT commercial usage. (The unfortunate side effect of producing an "open source" version would be some other commercial org will undoubtably "borrow" the FOSS code and use it to create their own locked down version!) However, low bitrate codecs tend to be relatively complex, and sound rather "quaint" (and thats putting it mildly!) Cant imagine too many HAMS want to dabble in ALL of the requisite technologies. (I might be wrong ... over time I have 'dabbled' in all these things, but not as a HAM.)(In fact, some aspects of tech are getting well beyond "Amateur" status. PCB design using BGA packaging -> actually getting the devices down reliably is probably beyond most Hams. Its not even easy for many companies during the "prototype" phase of design. Yet this is effectively the type of tech required to implement much of the stuff you have mentioned.)

I do not understand why there are any restrictions regarding SS. (Well, on bands above 70 cm anyway) ... These have obviously been mandated by government "spooks" attempting to cork the genie in the bottle. (SS is fairly obviously related to encryption ...)  These restrictions are more to do with government paranoia than with any basis in real life. (SS has been used by the US military for a long time ... and they sort of managed to keep it 'secret' for a fair percentage of that time period. (I might add that it was fairly obvious that there was something scrambling USA military signals ... since a spectrum analyser "listening" around 300 MHz would show there was something broadband jumping out of the general noise floor ... even though it still looked like "noise".) "Note to Government ... the cat is well and truely out of the bag!"

This discussion would probably be more appropriate on some HAM forum I suppose ... so even though I could say much more, I will leave it here.