RFI Snapshots

Annotated 40 meters showing RFI, click to enlarge

This page contains links to many SDR RFI Snapshots, of various sources of RFI as viewed using either a SDR, or a spectrum analyser. The RFI snapshots were taken by various people, using various equipment, of any number of RFI sources, all of which have been positively identified.

While this is not a explicit fingerprint, it can help in deciding what one is looking for with regards to an RFI hunt. I am not a fan of the RFI snapshot fingerprint method for identifying RFI, but it does help… For instance, if the source comes on and goes off each day, shifting only a few minutes per day, I would suspect lighting controlled by solar cells… Street lights, etc… If it is on a timer, and starts everyday at the same time, then I would suspect a grow operation. If only on windy days, then maybe power lines, etc… Another good use of this method is to track an already located RFI source. Once you have the fingerprint, you can tell if things are changing in the general environment of the source. It is sensitive enough that even a door left open will show a change in the day to day pattern. A great deal can be learned from looking at an SDR RFI Snapshot, but, it is not a substitute for actual RFI direction finding. It is only an indicator that can assist you in your Direction Finding, in helping to know what to look for. For more information on how I have been locating RFI see the three part set of articles located here.

If you have SDR snapshots of known sources, please send them to me, include as much data of what the source is, and all you know about it.