Intruder Watch by DARC, Germany


We deal with non-amateur radio band intruders primarily in the shortwave bands allocated for exclusive or primary use by the Amateur Radio Service up to 30 MHz under the International Telecommunication Treaty and the german amateur radio regulations:

Frequency (kHz)


  7.000 -   7.200

40m band

14.000 - 14.350

20m band

18.068 - 18.168

17m band

21.000 - 21.450

15m band

24.890 - 24.990

12m band

28.000 - 29.700

10m band


In the national context it's regulated by Amateurfunkverordnung (AFuV), Anlage 1 (zu § 1 Nr. 6).

Cooperation partner of the German Federal Network Agency

Monitoring and reporting centre for foreign radio services within the exclusive amateur radio bands up to 30 MHz (shortwave, HF)


The Intruder Monitoring Unit of the DARC is the intruder watch of the DARC e.V. and deals with unauthorised use of our bands by other radio services within the framework of frequency monitoring.


At the same time, it serves as a reporting centre for the radio amateur community and in this function receives reports on intruders. On this basis, we consolidate the information and, if necessary, initiate official steps that lead to the shutdown of illegal transmissions.


Unauthorised use of the amateur radio bands occurs when a foreign station uses the 40-, 20-, 17,- 15-, 12- or 10-metre bands, because according to the international telecommunications treaty these bands are exclusively allocated to amateur radio.



About radio intruders


Intruders are, for example, radio transmitters or their harmonics, digital modes of operation - such as Morse telegraphy, radio teletype or multiplex transmissions from the military, embassies or international organisations - radiotelephony traffic from the circle of users just mentioned and private radio pirates in the SSB (single sideband), AM (amplitude modulation) and FM (frequency modulation) modes of operation, the most diverse digital modes of operation, over-the-horizon radars, ocean wave radars, drift net buoys or illegal taxi radio.


The Intruder Monitoring Unit is not directed against radio amateurs who, for example, do not comply with band plans or harass or insult other radio amateurs. We also cannot help with local interference, such as that caused by PCL or switching power supplies.

Three over-the-horizon radars (OTHR) are occupying wide frequency ranges in the 40m band (2021). © Photo: Daniel Möller, DL3RTL

Legal basis of our work


The Intruder Monitoring of the Deutscher Amateur-Radio-Club e. V. is the German branch of the "International Amateur Radio Union Monitoring Systems" (IARU-MS) according to the IARU Resolution 12-1 "Terms of reference for the IARU Monitoring System".





We are in close and long-standing contact with various institutions, which we can address directly and involve directly via short channels, including offices of the radio measurement service of the german PTT (BNetzA).



Prüf- und Messdienst

Latest news

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KTWR Guam with intermodulation product on 10123 kHz

November 24th 2023


KTWR Guam is causing interference in the afternoon until 1600 UTC on 10123 kHz in AM with an emission generated by an intermodulation product at the transmitter site. Original transmission on 9900 kHz.


The Intruder Watch of the DARC has already involved the Federal Network Agency (BNetzA).


Daniel Möller, DL3RTL

Employee Sven Krüger (DF2KS) silent key

Photo: private

October 31th 2023


We mourn the loss of our employee Sven Krüger, DF2KS, who passed away completely unexpectedly on 29 October 2023 at the much too young age of just 38.


Sven had been an important part of our team since summer 2021 and was involved in many areas. In addition to monitoring and radiolocation, he was also our contact for data protection.


We got to know Sven as a prudent, quiet and empathetic colleague whom we all greatly appreciated.


Sven leaves behind a wife and two minor children. Our sympathy goes above all to his family.


He will always be remembered.


Daniel Möller DL3RTL
head of Intruder Monitoring DARC e.V.
and the entire team


OTH radar Ghadir interferes massively on 10m

September 27th 2023


The over-the-horizon radar (OTHR) Ghadir from Iran is currently causing massive interference again in the 10-metre band. At the current time (27/09/2023, 1000 UTC), for example, it can be found on the frequency 28500 kHz. With its broad signal, it is interfering with SSB traffic there. This is particularly annoying when conditions are high and QSOs are disrupted as a result.


e continue to ask for receipt reports.


Submit report


Daniel Möller, DL3RTL

Intruder Monitoring 2023 conference

From left to right
Back row: Daniel Möller (DL3RTL, Referent), Uli Schwertges (DL1US), Alex Schill (DB3TA, stellv. Referent),
Norbert Göttsche (DL8LAQ), Sven Krüger (DF2KS, sk)
Front row: Jürgen Lederer (DL2SCH), Andreas Hansen (DK7RCA), Erwin Zens (DL2KCW)


August 27th 2023


This weekend, nine members of our core team met in Baunatal.


During the two-day conference, we used practical examples in workshops to deepen our skills in radiolocation and the interpretation of national and international band plans and frequency allocations. We also focussed on training internal processes to further consolidate them.


On Sunday morning, we took the opportunity to visit the office in Lindenallee. Routine maintenance work was also carried out on the measuring and receiving station (MES).


The weekend was very productive and the second event of this kind organised by our young department, which emerged from the HF department's band watch in 2022.


Daniel Möller (DL3RTL), Speaker of Intruder Monitoring

"Splatter machine" again active

July 12th 2023


The wideband system with the working title "Splatter Machine" has now turned up again for the first time since spring 2022. This time on 18101 kHz on 12.07.2023 at 1840 UTC.


The particularly broadband system consists of ten individual data streams and is easy to recognize in the waterfall.


We kindly ask for reception reports.



Snapshot: DL8LAQ

Spanish fishermen on 21,000 USB

May 7th 2023


Spanish fishermen are observed on 21.000 kHz in USB on many afternoons in Central Europe.


Our translation service found that in European Spanish they were talking about cod, ships, an ice cream machine and going back to a port.


The DARC intruder watch has sent a notification to the Federal Network Agency (BNEtzA).


Sumit reception report


Daniel Möller, DL3RTL

FSK intruder on 7080 kHz and 7088 kHz

September 8th 2022


In our exclusive shortwave bands, there are always foreign radio services that really have no business being there. Sometimes they are difficult to be recognise.


Like in the case with the evening transmissions on 7080 kHz. At first glance, it seems to be RTTY and a legal amateur radio signal. But far from it. If you take a closer look at the parameters of the transmission, you will notice that it is a non-amateur radio FSK procedure. The step rate is 50 baud with a shift of 200 Hz. This method, called CIS-50-50, is mainly used by the Russian Navy.


We are preparing a new report to the Federal Network Agency (Bundesnetzagentur) and ask for reception reports from the ranks of radio amateurs and SWLs.


Sumit reception report


Daniel Möller, DL3RTL

Telediffusion d'Algerie interferes in the 40m and 15m band

August 4th 2022
update August 15th 2022


Algerian Radio has made a frequency change and is now broadcasting with its lower sideband of its A3E signal the 40m band in the early morning hours on 7200 kHz.


The German intruder watch has already involved the Federal Network Agency BNetzA to obtain the withdrawal of the frequency change.


Since 15.08.2022, the station has attracted attention with its Arabic programme on 21450 kHz. In the period from 1600 to 1800 h UTC, it interferes with its lower sideband in the 15m band. further transmission took place on 26th and 30th of August 2022.


Daniel Möller, DL3RTL

Radar in the 10-metre band

May 8th 2022


In the 10-metre band, conditions are gradually improving again. In addition to interesting radio conditions, this also means that intruders are becoming more noticeable.


Currently we have problems with an over-horizon radar (OTHR) from Iran, which causes interference especially at the beginning of the band with its broadband signal. It is highly likely that this is the Ghadir radar. The intruder monitoring unit is already working on this issue and is looking forward to receiving reports.


Submit reception report


Example May 8th 2022, centre frequency (CF) 28,200 kHz, bandwidth (BW) 46 kHz, 307/870 sps:


© Alex Schill, DB3TA
© Alex Schill, DB3TA

Alex Schill, DB3TA

Reporting form

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Report intruders to the intruder watch of DARC


Any radio amateur or shortwave listener can report intruders - i.e. non-amateur radio stations, no electromagnetic interference - to the band watch at any time using the report form. This is independent of a membership in the DARC e.V..


In the report form there is also the possibility to upload a screenshot of a waterfall diagram. Unfortunately, entries by e-mail cannot be processed.

Your data will be transmitted electronically to the band watch and managed there in a digital system. This system automatically triggers an alarm and notifies all service staff of the band watch by e-mail and directly as a message on your smartphone.

It only takes a few minutes from the time you submit your report to the time the service team is informed. As a submitter, you will receive an email from our system immediately after submitting the form, with a link where you can view the progress of the processing or make additions online at any time.


According to availability and time of day, the staff will begin to condense the information, compare it with other reports and, if necessary, ask the submitter questions. Experts in foreign languages and digimodes are also involved if necessary.

If all the information is available and it is a new intruder (foreign band intruder/radio service), the data set is transmitted to the BNetzA via a coordinated procedure, which in turn creates an observation case to confirm the foreign signal.


If the new intruder is confirmed, a so-called international complaint is usually sent to the corresponding country of origin.

Latest intruder reports

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The DARC intruder watch also reports its most important observations to IARU R1, where they are published in a monthly newsletter together with reports from other amateur radio associations in IARU Region 1.


Latest IARU MS R1 report

Contact persons

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The unit currently comprises 21 core staff from the areas of monitoring, analysis, radio directin finding, language translation, IT and project management.


Daniel Möller, DL3RTL

Speaker Intruder Monitoring Service of DARC e.V.
National coordinator

Alex Schill, DB3TA

Deputy speaker Intruder Monitoring DARC e.V.
Head of backoffice

Core team

Monitoring service


AlexDB3TAProcessing and profiling
DanielDL3RTLProcessing and profiling
NorbertDL8LAQRadio beacon monitoring
JürgenDL2SCHRadio beacon monitoring



Analyses service


AlexDB3TASignal analyses
DanielDL3RTLSignal analyses



Radio direction finding


ErwinDL2KCWTDoA and evaluation



Project management
System administration


DanielDL3RTLAgile projekt management, system administration, Webmaster



Data privacy


DanielDL3RTLcontact person for data protection



Language translation


The intruder monitoting unit has another team for translation tasks. Native speakers of a wide variety of languages (from Vietnamese to Russian to Brazilian Portuguese) are on hand to translate phonetic content to German language.


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The monitoring service and analysis staff are equipped with modern, professional SDRs. They also have access to a computerised, automated recording system.

The direction finding service will be equipped with its own remote and networked direction finding sites before the end of the year.

In the area of organisation and administration, we work with the latest project management software and ticket systems to manage and document the assignments.


(c) DARC e.V.

The Intruder Monitoring Unit of the DARC is divided into the Monitor Service, Analysis Service, Tracking Service as well as Translation and Project Management.

Monitoring service

The monitoring service is used to observe and log the HF bands for intruders. We make use of different sources for this.

We have technical possibilities for automated band monitoring. In addition, we receive reports from the ranks of radio amateurs, which reach us via the band watch reporting form. We call such reports community reports. They are processed in a modern electronic system.

It doesn't matter from which source the information comes: It is collected and condensed to create a profile of the intruder.


Analyses service

In monitoring, we are not always successful in classifying a signal right away. Sometimes there can be deviations or even new procedures. We have the relevant experience and resources to analyse such signals and assign them to a specific procedure.

Radio direction finding service

It is important to know where the foreign signal comes from. Only then it can be assigned to a specific radio service or originator with a high degree of probability. The DARC band watch uses the KiWi network with the TDoA function for this purpose.

In order to be able to achieve a consistently high DF quality, the band watch is currently setting up its own KiWi at locations far apart from each other. These are equipped with very sensitive antennas and are exclusively available to the intruder watch.


Language translations

Not all foreign signals can be assigned to digital operating modes. Occasionally, they are also transmissions in phonics. The intruder watch maintains a network of translators, including for Eastern European and Asian languages.


Project management, development and data protection

To operate our systems and design concepts for a wide range of tasks, the intruder monitoring unit has its own project management, developers and a contact person for data protection. We work in a structured way according to modern, semi-agile processes and with systems that are state of the art.



Radio monitoring station

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Learn more

A detailed description of our measuring and receiving station can be found on its own website.

System status

 Monitoring in service

 Direction finding
 on standby 

 Service team available 




  • Server with RAID 10 SSD Cluster
  • UPS for the entire setup
  • fire alarm system
  • Security technology

(c) Daniel Möller, DL3RTL

Technical equipment

The Intruder Monitoring Unit of DARC is the operator of its own measuring and receiving station. It is equipped with the most modern, software-supported systems and allows the automated monitoring and analysis of emissions on the shortwave bands.



Monitoring and analysis systems

At the software level, we work with e.g.


(c) Daniel Möller, DL3RTL

The hardware consists of


  • a commercial broadband magnetic antenna

  • an antenna splitter

  • sevaral SDR Winradio® G33DDC nad G31DCC

  • a server with

    • the monitoring software go2monitor®

    • Control software for the SDR

    • Control software for the antenna splitter

  • and various other support systems

Automated Radio Monitoring

The core of our system is the Procitec go2monitor® software. It allows us to scan shortwave frequency ranges for emissions in real time. The system simultaneously records all signals and classifies them. The parameters of the emissions are written into a database and stored there for further evaluation.



(c) DARC e.V.
(c) DARC e.V.
(c) DARC e.V.
(c) DARC e.V.


The following video shows part of our facility in operation, using the 40-metre band as an example:


Procitec go2monitor® in use at the Intruder Monitoring of DARC e.V.

Club station DLØIMO and DR5ØBAWA

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DL0IMO is the club station of the Intruder Monitoring Unit (intruder watch).

DR50BAWA is the special call and 50BW the special DOK for the 50th anniversary of the band watch of the DARC e.V.

Intruder Monitoring on the air

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The Intruder Monitoring team is also QRV on the bands under the call DL0IMO.

IMO stands for Intruder Monitoring.


DL0IMOIMOvia bureau


Radio contact will be exclusively with intruder watch staff.

We look forward to contacting you and confirm QSL cards via the office.

Special call sign DR50BAWA and special DOK 50BW

The Bandwacht celebrates its 50th anniversary in 2022.


To mark this occasion, from 01.01.2022 to 31.12.2022 we will issue the special DOK 50BW

and work with the special call sign DR50BAWA.


Callspecial DOKQSL
DR50BAWA50BWvia bureau


Contacts will be made exclusively with the intruder watch staff.
For every QSL card received, we send a special anniversary QSL card via the office.




You can find the activity dates under this link at


We confirm contacts with a QSL card via the office.



(c) DARC e.V.

Selection of legal services

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We share the 80-, 60- and 30-metre bands with other radio services, which may have priority and which we have to avoid.

BandFrequency (kHz)IDModeITUSystemBandwidth (Hz) / ShiftBaud
all bandsall frequencies FMCWdiverseIonosonde/chirpsounder  
160m1.814,00 J3E-L, J3E-URUSBRAS-3/RS-10  
160m1.896,50 PSK-8DSTANAG 428524002400
80m3.506,00 PSK-2ARUSAT3004D2400120
80m3.525,00 PSK-8AFLINK 11-SLEW24002400
80m3.527,00 F1BRUS 20050
80m3.532,00 PSK-4FLINK 11-CLEW600075
80m3.548,00 F1BRUS 20050
80m3.550,70 PSK-4, PSK-8ISR 240075/2400
80m3.553,80 PSK-8ATURSTANAG 4285  
80m3.581,80 PSKTUR 2400 
80m3.585,00 F1CTWNWX-Fax 120 rpm.800 
80m3.586,00 PSK-2AHOL 4040
80m3.593,70D (RCV)A1ARUS   
80m3.593,80P (RMP)A1ARUS   
80m3.593,80S (RIT)A1ARUS   
80m3.622,50JHMF1CJ 800 
80m3.631,00  ISRPSK-4, PSK-8240075/2400
80m3.752,00 PSK-8ATURLink 11-SLEW24002400
80m3.756,00 J3E-U?RUS   
60m5.361,80OUA15PSK-8DNKSTANAG 42852400 
60m5.355,70 PSK LINK 112400 
30m10.144,00DK0WCYA1ADAurora beacon  


Errors and typos excluded.



Helpful links

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IARU Monitoring System Region 1

Landing page of the higher-level monitoring system of IARU Region 1.

Website with sound samples of radio identification melodies.

Website of Martin Schöch with information on Clandestine Stations.

Introduction to Utility DX.


Ionosonde Juliusruh, Insel Rügen

Plot of the current ionogram*.

*Ionograms are graphical representations of the current state of the ionosphere in relation to a specific location or area.
We see the ionosphere with reflective layers (D layer, Es = Sporadic E, F1 and F2 layer, MUF = maximum usable frequency). N/A = not available = not available. The ionograms are updated continuously.


Explanation of the ionogram (PDF)



Ionosonde Dourbes, Belgien

Plot of the current ionogram.


Ionosonde Pruhonice, Tschechien

Plot of the current ionogram.


AKM Polarlicht Vorhersage

Link to the warning list.


DR2W DX-Propagation

Map of the current propagation behaviour.

Tropospheric overreach.


Überhorizontradar Wikipedia

Ausführliche Erklärungen zum Themengebiet Überhorizontradar.



General contact form

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We do not accept Intruder reports via this form.

To report an intruder please use the following form:


Intruder report form

General contact form

General contact form
By sending this form, I agree to the DARC e.V. privacy policy:

Secure Communication

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In order to communicate with the Intruder Monitoring Service in an encrypted way please follow these



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