Topband: K1N DQRM Tracking Project

[Jim Garland]

I agree, Lee. Locating a DQRM station involves accurately time stamping the
arrival time of their transmissions, at (at least) three receivers at known
locations. Once the arrival times are known, one can use trigonometry to
calculate the location of the interfering station. Since radio waves travel
about one foot in a microsecond, and since a microsecond is an eternity by
modern frequency counter standards, it should be possible to get very
precise locations. The city block mentioned earlier should be readily
doable. Of course, this requires that the three receivers be able to copy
the DQRM ground wave signal, since the arrival times would otherwise be
dependent on ionispheric reflections. More than three receivers would result
in more accurate position measurements.. There's no need to use direction
finding equipment, which are very low resolution by comparison with time
measurements..

I'm no authority on FCC rules, but I'm under the impression that
deliberately interfering with other licensed transmissions is against the
law. Every month or so, the FCC nails some renegade ham or CBer for doing
just that. Probably just publicizing the callsign of the culprits would be a
large deterrant for all but the most sociopathic offenders.
73,
'Jim

> -----Original Message-----
> From: Topband [mailto:topband-bounces at contesting.com] On Behalf Of Lee
K7TJR
> Sent: Sunday, February 08, 2015 4:47 PM
> To: topband at contesting.com
> Subject: Re: Topband: K1N DQRM Tracking Project
> 
> 
> Greetings top-band community,
> 
> Interestingly enough the technology exists right here in our own Ham
> community that could go a long way toward finding these DQRM culprits.
>     There are some beam forming arrays that operate with SDR technology
> where a recording can be made of a target bandwidth and later reviewed
with
> beam forming techniques to DF using a peak or notch completely after the
> event has long gone. In fact directional and strength data can be stored
in
> perpetuity.
>  So my comment is don't underestimate the ability to identify these
idiots.
>   Being able to actually replay an entire contest and do a strength and
> directional analysis in a narrow bandwidth after the fact to me is the
> ultimate receiving system.
> 
> Lee K7TJR   OR
> 
> 
> <I'd be interested in some project like that, but I'm afraid it would only
> get to a general area. With maybe 3-10 idiots at any one time, and the
3-10
> active at any time probably varying every hour, it might be pretty tough
to
> do anything meaningful.
> 
> Since attention is what they want, I wonder if this effort would not
> encourage participation in jamming at a faster rate than it solves
anything?
> 
> Has anyone ever looked to see if there is any correlation between
> intentional QRM and the DX station spreading people over a wide swath of
the
> band? More than once, I've heard people intentionally threaten to QRM DX
> because they were POed that their QSO was interrupted by a pileup.>
> 
> <73 Tom >
> 
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