Aficionados of digital communications are gearing up for the 29th annual ARRL/TAPR Digital Communications Conference (DCC), September 24-26 near Portland, Oregon. The ARRL/TAPR DCC is an international forum for radio amateurs to meet, publish their work and present new ideas and techniques. Presenters and attendees will have the opportunity to exchange ideas and learn about recent hardware and software advances, theories, experimental results, and practical applications.

The DCC is for all levels of technical experience -- not just for the expert. Not only is the three day conference technically stimulating, it is a weekend of fun for all who have more than a casual interest in any aspect of amateur digital electronics and communications; introductory sessions are scheduled throughout the conference to introduce new technical topics for both beginners and experts.

Topics at the DCC include, but are not limited to: Software defined radio (SDR); digital voice (D-STAR, P25, WinDRM, FDMDV, G4GUO); digital satellite communications; Global Position System (GPS); precision timing; Automatic Position Reporting System (APRS); short messaging (a mode of APRS); Digital Signal Processing (DSP); HF digital modes; Internet interoperability with Amateur Radio networks; spread spectrum; IEEE 802.11 and other Part 15 license-exempt systems adaptable for Amateur Radio; using TCP/IP networking over Amateur Radio; mesh and peer-to-peer wireless networking; emergency and Homeland Defense backup digital communications; using Linux in Amateur Radio; updates on AX.25, and other wireless networking protocols.

Each year at the DCC a separate (and lockable) room is provided for people to bring and show off their latest projects. Tables and power will be provided. Bring your equipment and display for all to see, learn and ask questions about. Be sure to bring a small sign and/or flyer naming and describing your project.

Sunday Seminar Speaker Announced

Each year, the DCC hosts an in-depth 4 hour seminar on Sunday. Past seminars have included such topics as Software Defined Radios, Spread Spectrum Design and Theory, RD Design and Deployment, PICmicro MCU Design and Development, Packet Radio Networks and others. Seminars are given by experts in their field -- this year is no different. Rick Muething, KN6KB, will present “DSP Tools, Techniques, and Tricks.”

The only prerequisite to attend the Sunday Seminar is an interest in Digital Signal Processing, though some experience in programming may be helpful. The only math you’ll need is the ability to add, subtract, multiply and divide -- and some idea of what a sine wave is. The goal of the workshop is to encourage those peripherally interested in DSP to take the next step to learn what DSP can do and to try some DSP design and coding. Each attendee will get a handout CD that will include all the slides, as well as links to useful references. The CD will also include some basic Windows VB.NET examples of operational code, along with some demo versions of useful DSP tools.

The Sunday Seminar will be broken into four 45-minute sessions with 15-minute breaks between each session. No seminar or workshop can cover this topic completely in a few hours, but this workshop should remove some of the mystery of DSP and motivate those to learn what can be done and get more involved:

• DSP Intro and Basics -- What we are trying to do with DSP? Why is it better or different than analog? Discover the cornerstone of DSP: the Fourier Transform and the FFT.
• DSP Tools -- What you need to see, interpret and understand signals. Basic waveform processing utilities. How do you setup a sound card to capture and play back audio (with examples)? How to design basic DSP Filters using common tools.
• DSP Techniques -- How do we use DSP to do those things needed in a radio? Mixing, filtering, modulation, demodulation, FSK, PSK, tone detection, AGC and the like.
• DSP Tricks -- Tricks of the trade to make the impractical possible. Common and useful tricks to make significant reductions in computer demands, Single tone detectors, decimation, windowing, CIC Filters and IQ sampling.

Muething is a retired entrepreneur electrical engineer and has been a ham since 1962. After volunteering for the Winlink development effort in 1998, he focused his efforts on programming and DSP. He was responsible for the SCAMP, WINMOR and V4 sound card protocols described in the DCC 2004, 2008 and 2010 Proceedings, along with several of the software components of the Winlink 2000 system.

Facility Information

Conference presentations, meetings and seminars will be held at the Heathman Lodge in Vancouver, Washington, about a 20 minute drive from Portland, Oregon. TAPR highly recommends that participants book their rooms prior to arriving. A block of rooms has been set aside for the DCC at a special rate of $89 single/double. This special rate is good until September 1; after this date, the regular room rate will apply. Be sure to mention group code DCC when making reservations.

Meals are not included in the registration. Two lunches and the banquet are available for purchase at the time of registration. Since numbers must be provided in advance to the hotel, trying to buy meals after arrival at the conference does cause difficulties. The banquet speaker will be announced at a later date.

The nearest airport is the Portland International Airport (PDX). The Heathman Lodge will provide a complimentary airport shuttle service as a part of the DCC (this is normally not a free service). Shuttle service is available from 0600-2300. A 10-day minimum advance reservation is required. Same day shuttle requests cannot be guaranteed but will be accommodated on an availability basis. For reservations please contact shuttle reservations via e-mail.