Innovator Ulrich Rohde, N1UL, Donates Sophisticated Vector Signal Generator to ARRL

02/18/2021

ARRL Life member Ulrich Rohde, N1UL, donated Rohde & Schwarz SMBV100A vector signal generator to the ARRL laboratory. The device offers internal signal generation for all major digital radio stations. “This is absolutely great news and extremely generous,” ARRL CEO David Minster, NA2AA, told Rohde.

The head of the ARRL lab, Ed Hare, W1RFI, said the tool would be a valuable addition to the lab’s testing capabilities.

“We will be able to do more comprehensive tests on modern radio stations, almost all of which use software-defined radio technology,” Hare said. “We will also be able to add testing of the digital capabilities of the receiver. The flexibility of this generator will serve the lab for years to come. “

Hare said he was happy to learn more about the SMBV100A once it was installed in the lab. “The potential is really exciting,” he said. “As always, we appreciate the support that Ulrich Rode has given to the laboratory over the last few decades.”

Rode said that vector signal generators are the logical successors of older AM / FM modulation signal generators and have virtually unlimited usability. “For some of the tests needed to characterize software-specific radio (SDR), we need different testing equipment,” he said. Rode noted that the SMBV100A has a built-in random wave generator capable of operating up to 6 GHz, with “very complex signals in it and also the familiar AM / FM simplified mode”

Moving from analog to digital SDRs, high-signal behavior is best determined by special multi-carrier signals, Rode said. Instead of a two-tone test signal for, say, measuring IF characteristics, the SMBV100A can generate up to 30 discrete tones. Rode said that the SMBV100A can generate any signal “as long as you can describe it mathematically”, even an FT8 signal. The bottom line is a more realistic test result.

Rode said that in 1982, while heading the RCA’s Department of Defense, he and his engineering team “invented what is now called software-defined radio,” which at the time was considered classified military information. .