[Elecraft] Babies at play as seen on the P3

[Ken G Kopp]

Do a Google search for "Digisonde" for additional info.

There are hundreds of 'em.  They play an important role in the WWV
predictions.

FWIW, I used to work at the University of Colorado's radio astronomy
department ... right across the street from NBS.

On Sun, Oct 29, 2017 at 4:37 PM, Drew AF2Z <pubx1 at af2z.net> wrote:

> There are ionospheric chirp sweepers that go through the hf spectrum every
> couple of minutes. They sound like someone lightly clearing his throat.
> Have no idea what it looks like on the pan display. On a given frequency
> you'll hear the chirp at the exact same time every couple of minutes
>
>