It is with great sadness that we bid farewell to Wolf, who passed away on 17 June 2025 at the age of 79. He was one of the most dedicated and distinguished guardians of the amateur radio frequency spectrum, championing the protection of amateur radio bands with expertise, perseverance and passion for decades.
Wolf was not only an exceptional radio amateur, but also an invaluable member of the international monitoring system. His decades of voluntary work for the DARC, particularly as head of the DARC Band Watch and later as coordinator of the IARU Monitoring Service Region 1, were characterised by his tireless efforts to combat interference, illegal transmissions, and commercial intruders on the frequency bands used by the amateur radio service. Alongside Peter Jost, HB9CET, the deputy coordinator of IARUMS Region 1, who passed away on 3 January 2025, Wolf monitored so-called band intruders and published the IARU Monitoring System’s monthly newsletter.
With technical sensitivity and an almost detective-like intuition, he identified sources of interference, such as over-the-horizon radars, military data links, illegal stations, and poorly suppressed switching power supplies. His well-founded reports were feared not by radio amateurs, but by those responsible for unauthorised transmissions, which he documented and reported with meticulous precision. He stopped numerous international disturbances on his own initiative, often within a few days.
His achievements did not go unnoticed. In 2013, the DARC awarded him the Horkheimer Prize, the association’s highest honour. In 2020, he received the IARU Diamond Award in recognition of his services to the protection of the amateur radio service worldwide. However, awards were never important to him; he was motivated by the ideal of a clean, free frequency spectrum for all radio amateurs.
His educational impact is also particularly noteworthy. Wolf made monitoring easy to understand. Through his presentations, articles and his renowned collection of ‘intruder sounds’, he conveyed his knowledge with great enthusiasm. He was a mentor, role model and point of contact for a whole generation of radio amateurs.
When he retired from active band monitoring at the end of 2019, he left behind a monitoring system that continues to have an international impact – a legacy that will endure. His call sign, DK2OM, will be missed, but his work lives on.
Rest in peace, Wolf. You deserve radio silence.
Tom Kamp, DF5JL
Former chair of IARU-R1 HF Committee
and current HF Officer of the DARC