browser icon
You are using an insecure version of your web browser. Please update your browser!
Using an outdated browser makes your computer unsafe. For a safer, faster, more enjoyable user experience, please update your browser today or try a newer browser.

RFI Mitigation

The RFI Mitigation category contains many articles dealing with the mitigation of RFI in the home, and in the field.  Includes articles on data capturing, Direction Finding, Loop construction etc.  Covers subjects such as how to record RFI levels, how to perform a full site survey looking for RFI, using SDR, how to clean up your shack of RFI generating devices, and many other articles…  Links to various other RFI mitigation sources are provided as well.

Building a coax entry panel

Loading

Overview: A year or so ago, I got the idea of installing a loop antenna to help reduce some of my RFI.  Not wanting to follow some of my previous bad practices with more bad practice, I decided to totally rebuild my coax entry method.  This led to the creation of a patch panel, and … Continue reading »

Categories: Cleanup, Construction, Info, RFI Mitigation, Station, Tools | Leave a comment

Notes: tinySA

Loading

I still want the expensive HP type of Spectrum Analyzer, but alas, I doubt I will have $40,000 bucks to throw at it.  When I saw the “tinySA”, (tiny spectrum analyzer), come to market a few months ago, and saw that R&L was selling them for $54.98, I just had to have one…  This entry is a string of notes that may help the next person along this route to get to a working, fully updated, with tools tinySA. Continue reading »

Categories: Accessories reviews, Direction Finding, Info, Notes, Quantification, RFI Mitigation, RFI Signatures, Setups, TinySA, Tools | 11 Comments

Elecraft K3: KSYN3A synthesizer installation notes

Loading

Overview: At one point, myself and K7OLN were living about 700 feet apart.  Both of us were very active, and as a result could not operate on the same band at the same time.  I purchased an Elecraft K3, and that helped, K7OLN then purchased a K3 and that helped more.  Then Elecraft came out … Continue reading »

Categories: Cleanup, Elecraft K3, Info, Setups | 2 Comments

RFI Site survey – Part II, interpretation

Loading

This is part II in a series of articles which will cover how I interpret and use SDR captured spectrograms as they relate to my RFI mitigation efforts.  See Part I, Using a SDR as a Site Survey Tool for how I setup and use the SDRPlay RSP1 as my SDR of choice, while using HDSDR as the radio control program.  The concept was to view my RFI environment as a whole, not in realtime, but across long periods of time, and very wide frequency spans. Continue reading »

Categories: Education, I have RFI: Series, Info, RFI Mitigation, SDR as Site Survey tool | 1 Comment

RFI Snapshots

Loading

Clicking on any of the images on the RFI category page will take you to yet another page, which contains any number of RFI signatures.  This may be helpful in identifying a source of RFI.  While it is not a a RFI fingerprint, it is an indication of what may be causing your RFI. Continue reading »

Categories: I have RFI: Series, Info, RFI Mitigation, RFI Signatures | Leave a comment

Using a SDR as a RFI site survey tool

Loading

Over the past several years it seems I have done nothing but hunt RFI sources. This process reminds me much of the old childs game called “Whac-A-Mole”. So the use of a SDR came to mind… This is how I set up an SDR site survey tool. Continue reading »

Categories: Cleanup, I have RFI: Series, Info, RFI Mitigation, SDR as Site Survey tool, Setups, Tools | 1 Comment

I have RFI, now what– Part I, Locating it

Loading

This allows me to verify I am working with the same RFI source. I record the audio from the FT-900, and then I can play it back into Spectrum labs, and see if it matches the RFI I am hearing at home. Once I have a match, I know without a doubt I have the same source. I then look at the map, and it becomes pretty obvious where the RFI is most of the time. I next start running the frequency up as high as possible and still hear the RFI. I then grab a Google Map of a smaller area, around where the signal is strongest, and do the drive around again. I repeat this process moving ever higher in frequency. Continue reading »

Categories: ARRL, Direction Finding, DX, I have RFI: Series, Info, Legal Actions, MFJ: MFJ-856, Quantification, Reviews, RFI Mitigation, Setups, Software information, Station, W8VVV: S-meter Lite | 2 Comments

I have RFI, now what– Part II, House Cleaning

Loading

I then brought up each circuit one at a time… Remember I had all the major appliances unplugged, so this test is looking for the various vampire devices that suck electricity all the time, pretty much anything with a wall wart on it. First I brought up the kitchen. That caused no issues, so I started turning on lights, and plugging things back in. The first source of RFI I found was a set of LED lights I got from Walmart. They are the ones that look like a 100W light, and put out about as much light as a 100 watt light. I heard nothing from them on 80, 40, 30, or 20. However on all bands above 20, they put out a horrific spray of RFI. Had I not checked all bands between testing I would have missed this. OK I noted this in my log book, and put a note there to change them out later. I turned them back off, and plugged in the refrigerator, I got a bit of RFI, so I added a few 31 mix ferrites to the power cord, and that RFI did not return. Next the Microwave got plugged back in, again, a small amount of RFI, and again a ferrite or two took care of this. There were no wall warts in the kitchen, so that pretty well took care of things for the kitchen. Continue reading »

Categories: Cleanup, Construction, I have RFI: Series, Info, RFI Mitigation, Setups, Station, Tools | 2 Comments

I have RFI, now what– Part III, Quantification

Loading

Over the past few years my RFI problem has been getting worse and worse. 40 Meters was unusable due to QRM last year, I am only now beginning to be able to use 40 meters again. Other hams in the area, (1/2 mile away), closer to the source of the RFI have lost the entire HF spectrum. See the movie above. Hit play, and all looks well until about 22:30 GMT, which is about 3:30 PM in my local time zone. As you can see, the RFI goes off scale at that time. The S Meter reading for that signal is around 10 db over S9. It is also affecting three other hams in the area. One poor fellow is so close to it that all ham bands are wiped out, 160 Meters through 10 meters are unusable during this time frame. There is another ham located about 1/4 mile from the source, he has just moved in, and was unaware why his use of 40 meters was precluded due to RFI. So there are folks who have it worse than me in this! Note this is an older recording, currently the start time for the RFI has changed to 01:36, or 7:36 PM local time. All in all there are 4 and possible 5 hams affected by what is a single source, over one or two square miles, all from a single source. We have the general area pinned down, and this summer, (2014), we are going to locate the house, and either contact the owner, or request FCC assistance. Continue reading »

Categories: Cleanup, Construction, I have RFI: Series, Info, Legal Actions, Quantification, RFI Mitigation, Setups, Software information, Station, Tools | 3 Comments

Rebuilding the Shack– from scratch

Loading

In 2014 I decided to upgrade the station, I became retired in 2013, and my use of the station was no longer weekends, and holidays. I could use it anytime I wanted, day or night. I decided I needed a better radio, and a bit more desk space. After a lot of looking, the Elecraft K3 popped up on my radar. The K3 provided me with a better radio, and a bit more desk space, exactly what I wanted. At the time of purchase for the K3, I decided it was about time to do a station rebuild, starting with the station grounding , and working my way to the Coax, and finally the control lines. Continue reading »

Categories: Cleanup, Construction, Info, Quantification, Reviews, RFI Mitigation, Shack Rebuild, Station, Tools | 2 Comments