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RFI 20M PSK31 Frequency

Feb 8th 2015, 15:01

KE4NHW

Joined: Mar 17th 2012, 23:02
Total Topics: 0
Total Posts: 0
For about the last month or two I have noticed a strange interference pattern on 14.070 MHz. The interference pattern can be most clearly seen in the waterfall at about 1800Hz to 2050Hz. These lines are evenly spaced at nearly 50Hz separation. Also, when I do not have a strong PSK31 signal coming in these lines appear across the entire 3kHz of the frequency, again spaced at 50Hz intervals. I have tested and determined these are not computer artifact. The strongest of these occurs at 1931Hz, and could easily be confused with a carrier if it were alone. I have asked several times on the frequency, and individuals at very different geographical areas are also seeing the same interference pattern. Some areas confirming are Canada, California, and Europe.

I have run very thorough tests on this end and determined the cause of the interference is not here. Moreover the reports from distant locations at times that I am not transmitting confirms something else must be the cause. Has anyone else seen this, and does anyone know what it is? Finally, is someone looking into a solution for this interference or is it unresolvable? For any interested persons I can save and provide screenshots of the noise.

Thank you for your input on this and 73.
Feb 8th 2015, 15:13

KE4NHW

Joined: Mar 17th 2012, 23:02
Total Topics: 0
Total Posts: 0
I forgot to mention that the interference is very specific to that frequency: moving off frequency even the requisite 3kHz totally eliminates the pattern. Hopefully someone can solve this mystery and determine if there is a solution that the IARU or the FCC could pursue.

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