[ntp:questions] Building/cannabalizing a WWVB radioclock...

Dennis Hilberg Jr dont at spam.me
Sat Aug 4 18:46:02 UTC 2007

Pete Stephenson wrote:
> It may simply be easier to get a GPS 18 LVC and see if I can get it 
> connected and seeing if it'll reach a nearby spot where I can get 
> signal. Either that, or get a "proper" WWVB receiver with a better 
> antenna.

I recently purchased a Garmin GPS 18 LVC for the purposes of a refclock. 
After soldering all the wires to a 9-pin serial connector and getting power 
from a USB port, I connected it to my Windows machine and used the Garmin 
SNSRCFG software to test it out.  To my surprise it had locked on to 8 
satellites, and currently seems to vary anywhere from 3 to 10.  I had plans 
to mount it outside a window or possibly on the slope of the roof, but from 
the looks of it now I can leave it sitting on top of my Linux machine where 
it is currently connected, with the 5 meter cable still coiled up in a twist 

I don't have any long-term data yet, as it's only been two days, but so far 
it works great.  Offsets average about +- 15 us, and jitter and noise are in 
the 1-2 us range.

So you might try the GPS 18 LVC as you just might get good signal, even 
indoors like mine.

Dennis Hilberg Jr <timekeeper(at)dennishilberg(dot)com>

NTP Server Information: http://saturn.dennishilberg.com/ntp.php

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