[RFI] Using an SDR to locate RFI

Dave Cole dave at nk7z.net
Mon Dec 12 12:53:34 EST 2016

How odd you should mention the SDRPlay right now...  I put up Part One 
of a at least a two part series on using the SDRPlay to characterize the 
local RFI environment, a few weeks ago...



If you have any setup questions, please feel free to email me.  We can 
swap phone numbers and I can assist you in setting up the SDRPlay.

The display shown on the web pages, shows long term RFI, as an average 
over time, vs. frequency.  Using the SDRPlay select about a 3 or 4 MHz 
wide area and start there.  If you get too wide, the RFI can get lost, 
and if you get to narrow the coincident RFI us not shown...

You will need to speed up the scan rate, (time wise), to see your 
sparking in real time.

You might give it a run as described and let it capture 24 or 48 hours 
of RFI.  The resultant spectrogram is very useful in getting a feel for 
your environment, and will show you how many of your RFI sources are 
connected to each other...  You may also see a pattern in your sparking, 
which could help you in locating it.

73s and thanks,

On 12/12/2016 08:19 AM, Frank N. Haas KB4T wrote:
> For the last several months, I've been trying to use an SDRPlay SDR
> Receiver with 3 different software packages as a tool for locating arcing
> and other forms of interference to the HF and VHF spectrum. I have
> virtually nothing to show for the effort.
> For over a decade, I've been using an ICOM IC-7000 mounted in my work
> vehicle with a Hi-Q 4/80 HF screwdriver antenna, a VHF 3 dB base loaded
> mobile antenna, a 5 dB center loaded UHF mobile antenna and an antenna
> switch to effectively drive to within 1 pole or 1 structure of the source.
> The system has served me well and made my (nearly daily) interference
> location work efficient and easy.
> The IC-7000 is long in the tooth. While I enjoy cashing the Social Security
> checks for the rig, I admit I'm spoiled by the enormously informative
> spectral displays provided by SDRs. It's time to retire the 7000 and
> install something new. The SDRs seem like the perfect, reasonably priced
> solution. Yet the SDRs are so efficient at masking noise that it's nearly
> impossible to use one as a locating tool.
> But my experience is limited to the SDRPlay. I chose the SDRPlay because of
> its frequency coverage. I've tried SDRUno, SDR Sharp and HDSDR software
> packages. I've spent hours experimenting with the configuration of each of
> these software options and have not been able to find a setup that
> effectively, consistently and clearly displays arcing interference. What
> I'm looking for is the type of display one sees on an ICOM IC-756-II or
> -III spectrum display. Look me up on QRZ (KB4T) to see a picture of what I
> seek.
> I've tried an Anritsu and an HP Spectrum Analyzer and they lack the
> sensitivity or the mounting practicality to do what I want.
> There are many other SDRs out there. WinRadio, AirSpy and a boat load of
> other makes and models. HAS ANYONE ACHIEVED ANY MEASURE OF SUCCESS getting
> one of these smart boxes to provide a useful spectral display of arcing
> interference? If so, please share with this group!!!
> Thank you!
> Frank N. Haas KB4T
> Utility Interference Investigator
> Florida
> _______________________________________________
> RFI mailing list
> RFI at contesting.com
> http://lists.contesting.com/mailman/listinfo/rfi

More information about the RFI mailing list