[time-nuts] A loran-C signal movie...

Poul-Henning Kamp phk at phk.freebsd.dk
Tue Nov 25 17:46:05 EST 2008

I thought some of you might get a kick out of this too:

I set up a shell-script to snapshot the tek4014 window from my
"AducLoran" receiver every few seconds.

The I managed to get ImageMagick to turn a selection of those images
into an animated gif:


The first 100 frames are 4-5 seconds apart, thereafter the rate drops
to 1 frame for each minute.

Here is an initial allan deviation for the receiver, relative to
a free-running FRS-10 Rb:


The red trace is the averaged off-the-air measurements by the receiver,
the green trace has the linear frequency drift of the Rb removed.

More about the project here:


Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.

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