[Lowfer] HF data burst

[David L. Wilson]

> On Thu, Oct 13, 2016 at 11:34 AM, Dexter McIntyre W4DEX
> <dexter.mc at gmail.com
> > wrote:
> 
> > For probably over a year I have been hearing on multiple HF frequencies
> > what sounds like a momentary burst of 4 data pulses.   It often repeats
> > every few minutes then either quits or moves frequency.  A sample just
> > recorded on 60 meters at the link below:
> >
> > http://www.w4dex.com/hf-data-4pluse.wav
> >
> > I don't believe it's local as others at a distance have reported
> > hearing the same.
> >
> > Any idea what the source is?


Sounds pretty much like one of the modes of an ionosphere sounder.  There
are ones operated by Lincoln Labs in MA and also one in Wallops Island.  I
have monitored both up close.  They are not very high powered and basically
vertical so you generally have to somewhat close to one except in unusual
conditions ( I hear Wallops Is. here in Fredericksburg, VA and occasion the
one in MA.)   I will e-mail you a waterfall capture of one.