SOLVED: Identifying interference with oscilloscopes and software-defined radio

[djhuft]

Longest capture yet, approximately 40 hours.

Here I set the waterfall to its longest time span possible, 48 hours, in hopes that I could see some daily patterns.


I have noted the approximate times of night and day here, which may correlate with some interference. Nothing really stands out though.

One interesting finding is that the strong 25 kHz signal I have been mentioning has been consistently present, until now. Here you can see the following, circled in purple:

• Disappeared at about 06:50
  
• Reappeared at 11:30
  
• Disappeared again at 12:00
  
• Reappeared at 14:30 and has remained since then.
  

(I added the time information from tooltips that I can see if I hover my mouse in GQRX.)

Anyway, it is possible that this signal can go away! I have no other clues about its origin just yet.

I would really like to make a portable sensor that I could use to do direction finding and triangulation to pinpoint the source. I'll keep you posted..