[RFI] "Marker RFI"

[N4ZR]

Here's an odd one.  I seem to have a new emitter in the neighborhood.  
It puts out a broad, T7, rough-but-steady tone just below 50 KHz 
increments (7000, 7050, etc.) .  It is loudest on 40M - about S4 - but 
audible from 80M up, and varies with which antenna I'm using.  It peaks 
due east on 20M on my tribander, and the difference between the 
zero-beat frequency of the "carrier" and the 50-KHz intervals on my K3 
diminishes with frequency, which suggests the possibility of harmonic 
origin of some sort.  I can also see it very clearly on my Red Pitaya 
122-16 SDR spectrum display with the K3 off.

Any idea what I should be looking for?

-- 
73, Pete N4ZR
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