Each March in the heart of the Pacific Northwest’s software capital, the MicroHAMS club hosts the annual MicroHAMS Digital Conference (MHDC). Having expanded beyond being Microsoft’s radio club, MicroHAMS now boasts members from all around the Puget Sound area, including a lot of digital innovators. This year’s conference was booked solid.
“I always come away from this conference energized and full of ideas about ways to put digital technology to work for ham radio,” said ARRL Contributing Editor Ward Silver, N0AX, who was a presenter at MHDC 2016. “This year was no different as the presenters focused on SDR and related technologies, including networking and fully digital radios.”
A challenging application of digital ham radio is to provide seamless race-day coverage of the RAMROD (Ride Around Mount Rainier in One Day) bicycle race. Curt Black, WR5J, described the perils of attempting data links around a 14,000 foot mountain surrounded by dense fir and hemlock forests, over a 150-mile race course with 10,000 feet of elevation changes. It’s not easy, but they do it and have bigger plans for 2016. The technology involves everything from 80 meter NVIS to 900 MHz RFID and D-RATS over the D-STAR system.
John Petrich, W7FU, is taking SDR into the UHF-microwave transceiver world with a design using the Ettus Research USRP B200 SDR and the GNU Radio Companion software platforms. The radio covers from 70 MHz to 6 GHz without converters and is an excellent “workbench” for someone interested in getting into SDR/DSP technology.
Alex Schwartz, VE7DSW, described his LiF/BiLiF adapter boards that use a conventional transceiver’s IF to create a fully functional spectrum scope. “It’s a particularly sweet combination with the FT-817 and can perform just about any type of modulation and demodulation you can think of,” Silver commented.
Two fully digital radios in late prototype stages also were shown. The HamShield by Morgan Redfield, KG7OGM, and Casey Halverson, KC7IBT, is not only a 144/222/432 MHz handheld based on the Arduino, but the project was funded through Kickstarter. The presentation was as much about the trials and triumphs of funding development as it was technical. Local company Northwest Digital Radio’s Universal Digital Radio UDRX is in pilot production after a long development and will have product available at Dayton Hamvention.® The 440 MHz transceiver is built to handle a wide variety of digital protocols and modulation types.
Following the ham radio presentations, Phil Horkin, AF7GY, gave a fascinating explanation of how MIMO (multiple input, multiple output) technology works. MIMO is commonly applied in the wireless data industry, in such devices as WiFi routers. MIMO depends on the presence of multipath propagation to work. Implementing it over line-of-sight links is the challenge, and Horkin is at the forefront of figuring out how to do just that, increasing a channel’s throughput considerably without consuming more bandwidth.
Silver said his own presentation discussed the changes ahead for ham radio, as new technology and new hams come aboard, taking Ham Radio 1.0 to Ham Radio 2.0. “It will be different but not unrecognizable, as hams carry the fundamentals forward into the second century of Amateur Radio,” he predicted.
“For radio amateurs, digital conferences such as this one offer opportunities to discover technology that is opening up little-used bands and achieving communication capabilities that were science fiction not long ago,” Silver observed. “The pace and breadth of development remind me of how packet radio and commercial wireless data developed with considerable overlap in the 1980s, a partnership that continues to pay dividends today.”
Presentations are available on the MHDC website. — Thanks to Ward Silver, N0AX