[RFI] ROTHR Interference?

[Paul Christensen]

For the past month, I've been plagued with a "chopping" interference between 
80m-30m.  The interference is not local, it's ionospheric.  This is not a 
form of interference you find by getting out and searching the neighborhood.

Ops from Florida are hearing this and I hear it being discussed on the 
80m/40m nets.  it started about three months ago.  It has the same level as 
the Department of Homeland Security's ROTHR system that detects illicit 
controlled-substance traffic in the Caribbean by triangulating pings from 
three high-power ROTHR systems located in Texas, VA, and PR.  I have not 
heard the usual ROTHR sweeps during this time.  This new form of sweep may 
have taken the place of the older ping that sweeps at a rate of 100 kHz/sec. 
That sweep sounded like someone transmitting a carrier and spinning the VFO 
knob at a constant rate.  The new sweep has a fast chopping component as 
well as fast pulses within each sweep.  This lasts for a bit over 2 minutes 
and repeats at different parts of the spectrum between 3-10 MHz.   If any of 
you recall the "Russian Woodpecker," it sound much like that system only 
with faster pulses.

Like the DHS ROTHR, it's us folk in Florida that get the brunt of it.  If 
you operate outside of the southeast U.S., you may not even hear it.

https://www.txarmymars.org/downloads/RaytheonRadarOverTheHorizon.pdf

I have attached a photo of the sweep at the opening of my QRZ.com page.

http://www.qrz.com/db/W9AC

Anyone know for sure if DHS changed the sweep pattern?

Paul, W9AC