SourceForge, Hamlib, and Rigserve... DCC'07

My contribution for the TAPR/ARRL Digital Communications Conference, Sept., 2007 appears here, as a PDF.

DCC is always a good show for advanced Amateur Radio technology. This year, it will be in Windsor Locks, CT, not too far from me. Previous Conference Proceedings are available.

SoftRock Antics

The "SoftRock" receiver kits have been around for a while. These are very inexpensive and basic quadrature sampler devices with a crystal controlled local oscillator. They make a complete receiver front-end for a Software Defined Radio. You can buy a version 6.2 SoftRock Lite kit from Tony, KB9YIG, for $10. I thought it was time to take the plunge.

For your $10, you get to spend hours putting together the tiny (1.5" square) printed circuit board, with a number of surface-mount components. After a little fussing, I got to the point of feeling some confidence with hand soldering the tiny components. The hardest part is organizing the right array of magnifiers to be able to see what is happening.

Here is how the board comes out:



I packaged it into a small aluminum box, and that was that!

To test it requires the following equipment: laptop computer, PowerSDR 1.8 software (from Flex Radio), a high-quality soundcard (I use the Edirol FA-66 Firewire box), and a good antenna (my 3-element SteppIR). With all that, we get the following view of the low end of 20 meters.

(Click on any image to see full resolution.)

Under normal band conditions, the SoftRock sounds just like my Orion transceiver. That is $10 well spent for self-education and fun. It calls out for a companion transmitter, so maybe the next step is to build a SoftRock Lite RxTx kit. Let's not get carried away - the RxTx kit costs $30.

Hamvention Video Clips

A couple of short video panoramas from the Dayton Hamvention!


In the Hara Arena -- a small part of the exhibit space.


The fleamarket scene.

Seen at Dayton Hamvention, 2007

Photos without comment from the Dayton, Ohio Hamvention, 2007. (Click for high-resolution versions.)

Is Ham Radio like a Telco?

Thanks to Slashdot for the following provocative video link. Van Johnson talks to Google about what comes after the TCP/IP Internet. In a nutshell, we have seen telco-style circuit switching morph into the current TCP/IP packet switched network, and the goal has always been to support end-to-end conversations. But the current Internet is dominated by fetching data (e.g. web pages), and TCP/IP is poorly suited for it. What will come next?



This talk leads me to ask what is "amateur radio" all about? Is it a way of supporting conversations? Of course, but is it more than that? Are we stuck in the telco model, a 100 year old paradigm? It is a problem if we are a hobby that only cares about "the wires" - or the airwaves -- and not about any higher level functionality. Food for thought.

On Older Rigs

Recently, I had a QSO with GP0STH, Ron, on Guernsey Island. Nice to have that new country! He gave me an unsolicited "great audio" report. Now, that was interesting...

I had just resuscitated my 30 year old Kenwood TS-520S to see how well the old rig was running. The Orion was sitting quietly on my desk.

The funny thing is that the Orion is well-known for great audio, and my Kenwood and its stock MC-50 microphone is not. But the Kenwood is the one that got that report. And its market value is about 1/15th of the Orion's!

Of course the Orion Rx is a lot better in difficult conditions, but on that day on that band (20 M), the '520 got the credit.

Among the kernel developers

Along with a number of other Linux users, I noticed that my Keyspan 49W 4-port USB serial converter stopped working when Fedora Core 5 updated to kernel version 2.6.18 late last October. Ever since then, I have not been able to update to the latest kernels. So, I reported the bug to Fedora's bugzilla (#21300), and sat back to see what would happen.

The bug percolated through the Fedora and Linux kernel support channels. At the end of December, I got word that the bug was probably found and a patch was put out for testing and inclusion into the Linux kernel. (I realize that if I really needed to use the latest kernels, I could apply the patch and compile driver for myself, but the fact is I don't need it that badly.)

Now it's March, and the patch has still not found its way into the mainstream kernel, as far as I can tell. I did not know what to expect from the process, but it does seem that progress is being made.

This post is really about my latest interesting discovery on this subject: a colloquy among the kernel guys about the progress of the patch. It gives a little insight to how things happen in the kernel world.

I do appreciate that people are working on "my" problem!

[Note added 3/16/07. The latest Fedora update included kernel 2.6.20-1.2300.fc5, which seems to incorporate the Keyspan patch.]

Birth of an Icon

Inkscape is a cool, open-source and free program for vector graphics drawing. It produces output in the SVG (scalable vector graphics) format, which is human-readable XML, and which can be used directly in future web pages. (Version 2 of Mozilla/Firefox, for example.) Inkscape is available for Linux, Windows, and Mac OS X.

I'm not a graphics pro by any means, but I was able to put this program icon together without much trouble. This is for our new project at rigserve.sourceforge.net.