Sweden’s Alexanderson alternator station SAQ said this week that a feed-line fire may have adversely affected the tally of listener reports from the station’s June 28 “Alexanderson Day” transmissions. Lars Kalland, SM6NM, at the SAQ World Heritage Grimeton site said there was a problem with the antenna on the first transmission from the vintage equipment at 0900 UTC.

“[A]fter a wet and rainy night between Saturday and Sunday, June 27-28, an isolator [insulator] in the antenna feed system, just outside the transmission hall, caught fire, during the startup and tuning of the Alexanderson Alternator,” a report on the SAQ website recounted. As a result, the transmitter was shut down, and no transmission was made at 0900 UTC.

Kalland blamed the incident on a short circuit and said the problem was able to be repaired in short order, in time for SAQ to return to the air for its scheduled 1200 UTC transmission. He said the SAQ team considered the 1200 transmission “one of the best transmissions ever,” and the frequency was clear of interference. SAQ transmits on 17.2 kHz.

The vintage SAQ Alexanderson alternator, dating from the 1920s — 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 number of Alexanderson Day reports was lower than usual, though — some 200 compared to the nearly 400 reports received after the Christmas Eve 2014 transmission. “Possibly the interrupted transmission is a reason,” Kalland speculated.

Out of the five US listeners who attempted to hear SAQ in June, only one — John Magliacane, KD2BD — was successful. He reported a “weak signal on [the] spectrum plot.” Far more reports came from all over Europe, with many listeners reporting a strong signal from SAQ.

The next planned SAQ transmission will take place on Christmas Eve, Dececember 24, 2015.