IARU Region 2 Monitoring System

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REPORTING  AN  INTRUDER


Reason For Reporting: Most intruders won't go off the air or move to a frequency outside of the Amateur bands by themselves. You have to actually do something to make this happen. If no one ever complains about an intruder, then he is not likely to move.

It is Important: Your reports of intruders are important and they are used by the Monitoring System in two different ways:

1. To identify the intruder by compiling and comparing information about the intruder from all of the reports received; and,
2. To form the basis of a complaint to the national administration or telecommunications authority in the country where the intruder is located.

Making Your Report: Some information is essential, as shown in the first table below. Please remember, to be useful your report should be as accurate and complete as possible, but even a very short report is better than no report at all. Use the summary on this page as a guide. 


Date and Time Date and time when the intruder was heard, in UTC.
Frequency Frequency of the intruding signal. 

This is a subject by itself, but following this guide will help you:
  • Give the carrier frequency for unmodulated carriers, on-off-keyed Morse, AM, SSB, and FM signals (in the case of voice and fax this is the resolution frequency or the frequency at which the signal sounds most natural).

  • Give the center frequency for RTTY and other frequency-shift-keyed signals, phase-shift-keyed signals, and for complex or unidentified modulations.
If you are not familar with these techniques, then just give the approximate frequency, as best you can.
Mode or Emission Describe the modulation method of the signal: CW, AM, FM, USB or LSB, FSK (as used for RTTY), PSK, pulse, etc. If you can, use the simplified table of ITU emission codes. Otherwise, just use your own words.
Remarks Describe any identifying features that you are sure of, such as language used, any callsigns or locations heard, program details, bandwidth of the signal (don't forget to account for your receiver's bandwidth), any apparent schedule of operation, and so on.


For some helpful information on measuring frequencies and determining the mode of modulation, see the Tech Stuff pages. Other helpful information can be found among the links on the Documents page.



For intruders in the downlink of an Amateur Satellite (see the article on VHF/UHF Intruders), the following information is also required:

Sat Name Name or designator of the satellite.
AOS/LOS Times of acquisition and loss of the intruding signal.
Real QRG Real frequency of the intruding signal (allowing for Doppler).



Other Useful Information to include: Besides the essential information mentioned in the tables above, there are some other details which are often useful to include in your report, such as:

Station Interfered With The name or callsign, frequency, emission, and location of the station with whom the intruder is interfering. This would be the station you were trying to contact or trying to hear. This information is especially helpful when a formal complaint must be prepared in accordance with ITU Appendix 10 (harmful interference) or Appendix 9 (irregularity or infringement).
Signal Strength Use the standard "QSA" code of 1 to 5, although any other common system, like "S", RST or SINPO will be OK. 
Frequency Shift
and
Keying Speed 		If the intruder is a digital signal, like RTTY, it is also useful to report the frequency shift and keying speed, if you can (not everyone has equipment or computer software which can measure these characteristics).
Antenna Sometimes, it is also useful to describe the antenna used to hear the intruder. If your HF antenna is a beam, include the direction or best beam heading to the intruder.

But don't get carried away. Most Amateur multi-band HF beam antennas at modest heights above ground are not very accurate for measuring the direction of arrival of radio waves, although with care and experience such a measurement can be reasonably reliable. Use your judgment.
Audio recordings, spectrograms, etc. Audio recordings in .wav format, captured screen shots of spectrum analyzer displays and other images or recordings of analytic material are often very useful for unknown languages and unidentified digital or complex signals. Try to keep the file size not too large (not everyone has high-speed Internet access).


Send Your Report!  Then send your report as soon as practical to the MS coordinator of your national Amateur Radio society, or to the IARU Liaison representative of your national society. See Contact the Monitoring System. If you are reporting intruders in a satelllite downlink, please also send a copy of your report to the IARU Amateur Satellite Coordinator, Hans Blondeel Timmermann PB2T, at pb2t@me.com.

Finally, if you have a large number of intruders to report, you might find it convenient to use a prepared form. 
A report form is available here in PDF format.

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