Despite mid-summer conditions, at least seven US listeners, most of them radio amateurs, were able to copy the 17.2-kHz signal from the SAQ Alexanderson Alternator at the World Heritage Grimeton Radio Station in Sweden. The July 5 transmission from the vintage electro-mechanical transmitter commemorated the annual Alexanderson Day. All told, more than 600 reception reports were received — a new record.
“The odds were not optimal this year, with the ongoing coronavirus pandemic, and in the early Sunday morning, the rain was pouring down, and heavy wind gusts made it hard to even take a peek at the antennas outdoors,” the report from SAQ said. “The transmitter hall was empty except for five members of the Alexander Association.”
Dating from the 1920s, the Alexanderson alternator — essentially an ac alternator run at extremely high speed — can put out 200 kW but typically is operated at less than one-half that power level. Once providing reliable transatlantic communication, it is now a museum piece and only put on the air on special occasions.
The transmitter was developed by Swedish engineer and radio pioneer Ernst Alexanderson, who was employed at General Electric in Schenectady, New York, and was chief engineer at the Radio Corporation of America.
Two Alexanderson Day transmissions were made. “On the first transmission, the rainy weather was making it hard at first to reach good output to the antenna, but after a few minutes with the ‘VVV VVV VVV de SAQ’ loop, the system started to dry, and the amps [antenna current] increased. Skies cleared for the second transmission later in the day, and, according to the report, the antenna current rose to 60 A, which ‘is optimal,’” the report said.
The occasion marked the inaugural transmission by Kai Sundberg, SA6KSU, at the helm of SAQ in a radio uniform dating back to the 1960s.
An article about Alexanderson Day, “The Legacy of Radio at Grimeton Station, SAQ,” appears on page 66 of the July 2019 issue of QST.