AA3B - DQRM

[4L5A]

As some of you know, I have been subjected to deliberate QRM (DQRM) in the WPX CW, IARU, ARRL DX CW and WAE CW contests. The DQRM operator uses at least two, and possibly more, remote stations in the USA. The DQRM operator will park on my run frequency and call CQ using V26K or other calls that are listed on my QRZ.com page. The DQRM operator will follow my frequency changes. The DQRM generally persists for hours.



The purpose of this message is to request your assistance in determining the location of the remote stations used by the DQRM operator. I received several heading reports from the 2025 ARRL DX CW contest that suggest one of the remote stations is in New England and one is near the southeastern coast of the USA. I am hopeful that additional headings will refine the source locations and therefore request your observations. Please send them to me at aa3b.bud@gmail.com <mailto:aa3b.bud@gmail.com> .



Thanks for your support.



73,



Bud AA3B

[4L5A]

Thank you for the deliberate interference (DQRM) observations from the 2025 WAE CW contest. I experienced DQRM during the 2025 WAE CW contest, but the signature was significantly different from pervious events.



First, the duration of the DQRM was much shorter. There were two periods of DQRM, lasting a total of 68 minutes, on 9 August 2025, as follows: 1241 to
1345 UTC on 20M and 1855 to 1859 UTC on 15M and 20M. The reverse beacon network reported at total 125 spots of V26K during these time periods.



Second, the location of the DQRM source was in Europe rather than the USA.
There were no spots of V26K by skimmers outside of Europe. A beam heading report I received indicates the signal was from a location southeast of the Netherlands, possibly from Italy.



Third, there was only one DQRM source active, as compared to at least two in the past.



A few other notes. I am appreciative of the network administrators at both RHR and RemoteHams.com who evaluated network traffic for possible matches to DQRM events I've experienced in the past; no matches were found. Also, I experimented with Time Difference of Arrival (TDOA) capabilities of the KiwiSDR network for location identification prior to WAE CW and found that it did not produce accurate location information for CW QSOs.



So, the hunt continues..



73,



Bud AA3B