Introduction - A small number of stations generate Deliberate QRM, known as DQRM,by transmitting on the frequency of a rare station in order to disrupt the operation. They do so anonymously, not identifying with their licensed callsign and thereby contravening the terms of their transmitting licence.They do not explain their motives for this anti-social behaviour, so the rationale for DQRM is poorly understood and perhaps can be viewed as anarchy –just disruption for the sake of it. But it can cause considerable inconvenience, even anger, to legitimate DX Chasers and is deemed a serious nuisance.DQRM is becoming an ever bigger problem these days.EASSYL-FBDA
One such DQRMer has been identified by the content of his CW transmissions. Over a period of several years this station has caused prolific CW DQRM to DXpeditions on countless occasions and for long periods. His CW sending is poor so the call-sign used is frequently sent as EAHSYL or FDDA (a varying number of CW dots). It might be that this individual is mentally deranged. Yet he is evidently an experienced DXer. His transmit frequency is fairly accurate and he often appears quickly on the frequency when a rare station starts to operate.
His CW sending is distinctive both in terms of his poorly constructed Morse code and the content of his messages. So he is easily identifiable, no matter which ‘call-sign’ he chooses to use on that day. His CW is hand-sent, not computer-derived, and is immediately identifiable. Although he uses different ‘callsigns’ we will refer to him here simply as EASSYL.
Direction Finding
A small group of determined DXers therefore set out to identify EASSYL, as the first step in identifying a number of persistent DQRMers. The first objective was to locate and identify this individual, then to arrange that he cease his disruptive activities. To achieve the first objective required DF. It was quickly established, some years ago, that the EASSYL signal emanates on a beam heading of about 120 degrees azimuth from UK. It was thought that this station was located in Southern Europe, possibly Italy, Greece or a Balkan country. Refining the beam headings we concluded that he was located somewhere in Italy.
A well-positioned radio amateur DXer is employed in UK with access to professional DF facilities. He joined our small, ad hoc investigative group and was permitted by his employer to track EASSYL when not otherwise engaged in his professional duties. This facility is extremely accurate, determining a heading to within two degrees azimuth and may simultaneously take automated bearings from several different sources (countries). The headings are automatically drawn on a map and the lines converge on one point, indicating the location of the signal within the range of a very few miles. This facility was used, during 2014, to help locate EASSYL.
The first map shows three sources of DF which converge on a point just West of Rome, Italy. The second map homes in on that area with five DF sources. The ellipse resulting has a small ‘pin’ at the statistically significant point where the source of the signal is thought to be located. This is a little to the East of Lido di Ostia.
DFing-DQRM - Identifying DQRM by G3SXW
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