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Monday, February 11, 2019

RFI Generator for RDF Practice

I have been having some issue with HF noise in my neighborhood. I would like to track this down and resolve it. The first thing that I did of course was make sure the noise was not coming from my own house. I did this by powering my HF radio with a battery while cutting power to the main breaker of my house. With the noise still present it seems to be coming from outside.

I think I might know the general area of the noise source from driving around with an HT in AM mode and finding a peak in the noise.

However before further investigation and since I am not very seasoned at radio direction finding I decided to get some practice with an RFI generator.

Information on the device I built can be found here:
http://www.w0qe.com/RF_Interference/simple_rfi_generator.html

I chose an oscillation frequency of 1 MHz. This covers the whole HF band and into lower VHF frequencies. I placed a socket on the board to allow the oscillator to be swapped out for different frequencies.
RFI generator assembly

The plan is to use this source with homebrew antennas directional and otherwise to hone my skill in finding these noise sources. Hopefully, I will be able to quickly and accurately locate real ones.

Snapshot of the RFI generator spectrum

Sunday, February 10, 2019

ARISS (02/08/2019) SSTV Event


I was able to capture some images this weekend sent from the ISS for its SSTV event. For those not familiar with it you can visit http://www.ariss.org/ for more information. My setup was a modest 2 meter mobile rig connected to a simple quarter wave vertical in the attic. I used a program called Mmsstv for decoding.  I have posted some of the images that I have captured below.















 (Updated: 2/16/19, ARISS redo weekend)