ARRL/TAPR Digital Communications Conference: "Pretty Interesting!"
Almost 150 aficionados of digital communications came to Chicago for the 27th annual ARRL/TAPR Digital Communications Conference (DCC) the weekend of September 26-28. This conference is an international forum for radio amateurs to meet, publish their work and present new ideas and techniques. Presenters and attendees had the opportunity to exchange ideas and learn about recent hardware and software advances, theories, experimental results, and practical applications. Not only was the conference technically stimulating, it was a weekend of fun for all who have more than a casual interest in any aspect of amateur digital electronics and communications; introductory sessions were scheduled throughout the conference to introduce new technical topics for both beginners and experts.
One of the attendees was QEX Editor Larry Wolfgang, WR1B, representing the ARRL. He gave a talk "Writing for Publication - It's Not Rocket Science (Even if You Are Writing About Rocket Science!)." Retired ARRL Chief Technology Officer Paul Rinaldo, W4RI, also represented the League, speaking on "SDR Outlook." Central Division Vice Director Howard Huntington, K9KM was present, as was ARRL Contributing Editor H. Ward Silver, N0AX.
Wolfgang gave his presentation on Friday morning and said he talked with many participants throughout the conference who told him that he had them enthused about writing something for QEX. "It also seemed like almost everyone there was making a point to stop me in the hallways or at mealtimes to tell me how much they are enjoying QEX, and to thank me for the effort I putting into the magazine," he said.
Friday was a full day of technical presentations, including "A Protocol for Multicast Weather Data Distribution over AX25," by Nick Luther, K9NL; "SuitSat-2 Update," by Steve Bible, N7HPR; "EcomScs and GateWayScs AX25 Packet Radio E-Mail," by John Blowsky, KB2SCS, and "Frequency and Other New Initiatives in APRS," by Bob Bruninga, WB4APR. The last presentation of the afternoon was "D-STAR Uncovered," by Peter Loveall, AE5PL.
The DCC provided a separate demonstration room for participants to bring and show off their latest projects. Participants were encouraged to bring their own equipment and display for all to see and learn. Wolfgang said he had some "play time" in this room after all the presentations on Friday. After dinner that evening, he said there was "a string of D-STAR presentations starting at 7 PM and lasting until after 10 PM. These were all very interesting presentations, including the D-RATS messaging software by Dan Smith, KK7DS. Peter Loveall, AE5PL, presented "D-PRS Update" about ways the D-STAR data links can be used to send and plot APRS position maps or interface to the APRS system. Robin Cutshaw, AA4RC, gave a presentation about DV-Dongle, a PC add-on that allows connection to D-STAR repeaters around the world through your PC and an Internet connection. Pretty interesting!"
In addition to the main technical presentations on Saturday, there was also a full day of introductory sessions, mostly about digital voice and D-STAR.
Also on Saturday, Matt Etttus, N2MJI, gave a report on the Ettus Research USRP2. Tom Clark, K3IO, gave an "AMSAT Update." Paul Wiedemeier, KE5LKY, presented his paper on "Using UDPcast to IP Multicast Data over Packet Radio." Paul Rinaldo, W4RI, gave his "SDR Outlook" that covered the international regulatory front and presented some of the concerns that some world governments have with regard to the flexibility of SDR. Scott Cowling, WA2DFI, gave an "HPSDR (High Performance Software Defined Radio) Update" during which he described the various circuit boards that make up the HPSDR project. He also demonstrated a complete working radio in the demo room. Jerry Shirar, N9XR, presented a paper called "Clocking the Data," concerning the use of an inverter and a crystal to form a Colpitts oscillator.
Victor Poor, W5SMM, gave an update on Winlink 2000. "He reported that there is one Web site, five Common Message Server sites around the world, 150 Radio Message Service Pactor Gateway sites, 800 RMS Packet Gateway sites and over 13,000 registered users," Wolfgang said. "He also mentioned that inactive users are purged from the system from time to time."
Rick Muething, KN6KB, described his "WINMOR Soundcard ARQ Mode for Winlink HF Digital Messaging." Wolfgang said that this was a much anticipated presentation: "Rick reported that WINMOR is 3 to 4 months from beta testing. His preliminary comparisons to Pactor 1, 2 and 3 use a simulator. He indicates that WINMOR will have better throughput than Pactor 1 and comparable to, or perhaps a bit better than Pactor 2, but not quite as good as Pactor 3. He indicated that the efficiency is within about 70 percent of Pactor ARQ."
The TAPR Annual Meeting was held after all the presentations on Saturday where the Board of Directors discussed the idea of coming back to the same hotel for next year's DCC. "The local group that supported DCC this year, including Mark Thompson, WB9QZB, and Kermit Carlson, W9XA, did a great job of providing AV support," Wolfgang said. "Ron Steinberg, K9IKZ, who owns a local audio/visual company, provided two large projection screens and projectors, so every presentation was shown on both sides of the room, as well as on a widescreen TV outside the room. The audio was very easy to hear, even if you were in the hall outside the room or in the demonstration room; the set-up was left there from the W9DXCC Convention the previous weekend. They offered to provide the same support for next year, if the DCC returned. So, the decision was made to break with tradition, and return to Chicago next year, September 25-27."
Phil Harman, VK6APH, presented the Sunday morning seminar, "Software Defined Radio Through the Looking Glass." Wolfgang said he found Harman's presentation to be understandable "at my level of knowledge, and he gave a lot of good insight into many of the design decisions that went into the High Performance Software Defined Radio Project. I found his descriptions of how the hardware and software work to be very interesting. The four hours went by quickly."
For more information on the 2008 Digital Communications Conference, please visit TAPR's DCC Web page.