ARISS International Chair article – APRS Inventor and Architect of ARISS Kenwood Radio Crew Interface, Bob Bruninga, WB4APR, Passes Away

APRS Inventor and Architect of ARISS Kenwood Radio Crew Interface, Bob Bruninga, WB4APR, Passes Away

The ARISS international team mourns the loss of Bob Bruninga, WB4APR, a genius who pioneered digital amateur radio techniques, invented the APRS digital signal protocol and designed the innovative ARISS Kenwood Radio Crew Interface. Bob passed away on February 7, 2022 after a fearless 2-year battle with cancer and, in the end, succumbing to COVID-19.

Bob’s brilliance permeated all through the amateur radio community, primarily via his invention of APRS, the Automatic Packet Reporting System. In Bob’s words, APRS is a “two-way tactical real-time digital communications system between all assets in a network sharing information about everything going on in the local area.” In APRS’ nascent days, Bob joyfully shared, in real-time through APRS, the annual midshipmen 230 mile “running of the football” from the US Naval Academy to the Army-Navy game football stadium. With the help of his Naval Academy students, Bob developed several innovative, low-cost amateur radio satellites that continue to be employed by hams worldwide. He promoted the development of a network of APRS satellites in low Earth orbit on a shared frequency—145.825 MHz—and he was proud that the ARISS radio station was part of that network. A replica of his first student satellite development, PCSAT/NO-44, is displayed at the Udvar-Hazy National Air and Space Museum in Northern Virginia, USA.

Bob’s contributions and creativity in Human Spaceflight Amateur Radio are many—spanning nearly forty years. In early 1985, prior to Astronaut Ron Parise, WA4SIR’s, planned flight on STS-51E in March 1986 (which was delayed after the Challenger accident), Bob worked with an AMSAT team to develop protocols and software for rapid message exchange via a packet “Robot.” In Bob, WB4APR’s own words, these “discussions helped firm up ideas on how APRS could be used not only as positioning tool, but also as a communication capability allowing rapid status and message reporting. Thus, allowing lots of people to rapidly make exchanges during a brief satellite pass.” The packet robot was used heavily in our SAREX (Shuttle) program, starting with Ron’s STS-35 flight in December 1990. APRS remains a key staple in our ARISS on-board systems.

In the early 2000s, when ARISS was developing its second-generation radio system, Bob became the chief architect of the ARISS Kenwood D-700 radio program modes (see above photo). Our chief requirement was to make the crew interface simple and easy to switch between operations modes. Bob distilled our requirements into an elegant crew interface with four program modes, to support school contacts, voice repeater, APRS, and experimental operations. Bob’s program mode crew interface is also embedded in our Next Generation InterOperable Radio System that employs the Kenwood D-710 GA radio system. Each time you use the ARISS radio system in any of its operations modes, you can thank Bob’s brilliance for making it happen.

On behalf of the ARISS International Team, I would like to convey our heartfelt thoughts and prayers to Bob’s wife, family and his many friends. Bob, we thank you for your unquenching drive to innovate radio communications and your pioneering spirit that transformed your brilliant ideas from a dream to reality. Because of you, your APRS signals continually serve as an amateur radio beacon of inspiration, hope and peace throughout the infinite universe.


Frank H. Bauer, KA3HDO
ARISS International Chair
ARISS-USA Executive Director



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