Tuesday, March 24, 2009

Out On The Perimeter

There are several other SDR initiatives happening. I am certainly NOT a catalog of what is going on.

There is a site called HPSDR that I spent some time with. In the days of the SDR-1000 there was a group that came together to develop what was presumed to be a cheap alternative to the $350 "sound card" that the SDR-1000 required. Note the present day Flex radios do not require any separate gear to perform. The "sound card" has been replaced by an A/D converter which is the function that the sound card performed and for audio duties codecs have been incorporated, so these rigs are stand alone except for the computer of course.

It turned out the "cheaper" sound card would up costing about $400 by the time it was all kitted out including power supplies etc. It was pretty high performance though. It was a monumental task (I just bought a couple of these I did not do the work). The boards were distributed by TAPR and if you go to that site you can still see them listed. It was an interesting experience and it became clear to me just how important having a company like Flex was. It was clear this endeavor would not be sustainable, and that has proven to be true. Because Flex is for profit it gives an ongoing enterprise which the community can rally around, and this symbiosis to me seems absolutely necessary to proceed to the future. If everybody is just a volunteer, its a lot like herding cats. The project is fine until you get bored. Because Flex is open to collaborators, l can collaborate share my data and the fertile ground of ideas gets plowed and fruit of those shared ideas grows. If you look back at the posts I have recently posted you can see this is the case. In this edition I hope to look at some of the other ideas floating around world regarding SDR.

HPSDR resides on its own board. There are a lot of interesting projects going on there, but in some respects it reminds me of the "hobby radio" kind of thing Flex was when it started. To see the projects click the tabs near the top of the page. The dark blue are nearing completion and the Cyan are "proposed" (aka day dreams). Very interesting stuff.

Here is a transceiver project built by Phil Harmon VK6APH, and give a taste of the high quality experimentation happening over there.


Phil is a mover and shaker in the HPSDR world and it is very cool to look at his skill set and see what he does. Go over there and peruse the place. They also have a reflector so you can follow along. If you don't know much about SDR following a reflector is a good way to pick up on concepts. Even if you don't quite get it, you will be exposed to the language and eventually things will start to make some sense.

Another SDR enthusiast has taken his interest into a commercial enterprise N8VB has produced the QS1R which is a high performance SDR receiver.

I love the look of this picture. My ten year old says it looks like a city.

So take a look over there and see N8VB's masterpiece. I think he has a transmitter in the works as well.

There have been a couple of clones of the SDR-1000 built and marketed. The latest is the Wonder Radio which is being marketed by an Indian company. This radio is basically a knock off of Gerald's article and capitalizes on PowerSDR as its brains. It has its faults, but I think one very interesting thing is there are a billion plus people in India, and in that billion people are a lot of kids who are driven to get ahead. I can see this as being a SDR laboratory that a kid could get his hands on and modify the code and modify the code etc and become really smart about SDR therefore assuring himself or herself a future. Ham radio is not just the US but it is a world wide enterprise. Imagine when there is a band grab for some ham frequencies the thing that SAVES us is the fact there are hundreds of thousands of Indian kids running their 1 watt knock offs and therefore there is tremendous usage of those frequencies so they should be preserved. Also just because we in the US are a bunch of old fart white men and we are dying, does not mean the hobby is dying world wide, not by a long shot.

I had some correspondence with some SDR types in Russia and they assure me there is a BIG interest over there. I know also there is interest in the old eastern block Soviet countries. So while your quacking about the weather on your latest Yahoo FT-25000 transceiver there is some kid over in India just itching to eat your lunch. I've been to China a couple times and this is absolutely true. In these developing countries they are leapfrogging over the old technology strait into the new, and those of us demanding things stay the same will be left in antiquity.

There was a company in Europe that started a SDR-1000 knock off but I think they went out of business. Now adays it is not trivial to get something like this off the ground. For example the European Union has adopted certain "standards" that erect effective trade barriers and tariffs, in other words hurdles you need to jump before you can market your radio there and hurdles are expensive to overcome. It takes someone with enough resources to mount these barriers. Even in the US to become type accepted required a number of barriers to be scaled.

A radio like the F5K has great potential to be set up as a frequency hoping kind of radio. In order to attain type acceptance the radio HAD to have a firmware layer inserted that stops the ability to do this. Why is this important? Freq hopping algorithms can be constructed that makes the radio virtually undetectable to someone who might want to listen in like the government. Not all ham radios get used by hams.

Lest I forget there are the softrock projects. Here is an article on the softrock rx/tx combo QRP rig. These Softrock rigs are the "every man rig of SDR" They provide a wonderful look inside of SDR at a ridiculously low price. Their performance is pretty much entirely sound card dependent, but there are plenty of sound card upgrades out there for not a lot of money these days. Included in the last article is a reference to yet another minimalist SDR console program called the "KGKSDR" This is just one of the many hobby type home brew projects out there. All you need is a couple hundred bucks some time and determination. I've built a few of the Softrock rigs. I've taken them on vacation along with my laptop. Its fun to flip a wire out the balcony or take the laptop out to a park and flip a wire into a tree and hear what you can hear. Their performance is totally dependant on the quality of the soundcard and horsepower in your computer. Given the horsepower that abounds these days those limitations are no longer limitations

There are probably a dozen other projects going on out there I don't know about. I have a hard enough time keeping track of the little I keep track of. There certainly are other software enterprises in motion including the GNU radio project and others.

If you search around I'm sure you will find much more to experience. Another goodie JAVA Console you tube JAVA Console blog As you can see much good stuff is out there. Radios are being built that can be distributed across computers so your DSP may be on one machine while your GUI is on another. This will be the case with the new PSDR architecture. It will also be platform independent. It will be as I understand it in ERLANG with I understand a healthy does of XML. ERLANG is interesting. You can replace whole modules in the program while the program is running....take out the right brain, put in Brian 2.0, kind of mind boggling (pun intended)

Above all go forth and have some Ham Radio FUN!!

73