[RFI] RFI Signature

[Michael Carter]

I generated a FFT spectrum estimate of Jeff's 'Noise 1a 20 kHz BW' audio file and attempted to post it to the reflector, forgetting of course that this reflector doesn't allow image content embedded in posts.   I sent that email direct to K9YC and W4DD, and hope that Jeff can add it to his Google Drive page.

For anyone wishing to generate their own spectrum estimate, I used Audacity with FFT size 8192 points, Hann windowing.  The 60 Hz line and its harmonics are prominent.

73,
Mike, K8CN
________________________________
From: RFI <rfi-bounces+mike.carter=unh.edu at contesting.com> on behalf of Jim Brown <jim at audiosystemsgroup.com>
Sent: Tuesday, November 25, 2025 11:12 PM
To: Rfi List <rfi at contesting.com>
Subject: Re: [RFI] RFI Signature

CAUTION: This email originated from outside of the University System. Do not click links or open attachments unless you recognize the sender and know the content is safe.


Can you do an FFT of this, Don?

Jim

On 11/25/2025 5:09 PM, Don Kirk wrote:
>    One is the oscilloscope display of your noise which I called "RFI
> being investigated" when you were using 20 KHz bandwidth.  T


_______________________________________________
RFI mailing list
RFI at contesting.com
https://nam12.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists.contesting.com%2Fmailman%2Flistinfo%2Frfi&data=05%7C02%7Cmike.carter%40unh.edu%7C696bbf5b697a4f76fe5008de2ca20a05%7Cd6241893512d46dc8d2bbe47e25f5666%7C0%7C0%7C638997271640725338%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=2UXcCxfn%2BHQuZRB4jF4WuUMOfYJ4TeRBWfOIzsc%2F3Y4%3D&reserved=0<http://lists.contesting.com/mailman/listinfo/rfi>