[ntp:questions] Inexpensive home reference clock - WWVB/CDMA?

Pete Stephenson pete+usenet at heypete.com
Sun Jul 1 22:17:37 UTC 2007


In article <000201c7bc28$9d92dd30$0a00a8c0 at Inspiron>,
 jason at extremeoverclocking.com (Jason Rabel) wrote:

> What GPS antenna did you use? Was it passive or +5V? What was the rated dB
> gain? Did you try sticking the antenna a few inches out past your window?
> Sometimes you can increase your signal dramatically just by doing that. Also
> depending on where you live if you only have a partial view you want it to
> face towards the equator for the most satellites.

All I have is a handheld GPS navigation system (Garmin eTrex). The 
window in my apartment faces another building about 15 feet away, and 
there's an overhanging roof. There's a sliver of sky coverage, and some 
signal makes it through the roof, but it's really not much. Sometimes 
there's moderate coverage from 3 satellites, while other times there's 
none at all.

> Maybe you could make friends with the person on the top floor and they would
> let you mount an antenna on a PVC pipe outside their balcony which would get
> you a clear view of the sky then you can just run the cable down the outside
> wall into your apt.

Apartment management doesn't take kindly to stuff like that, and the 
balcony is outside their front door (relatively small studios), so 
there's not really any sky coverage either (see the overhanging roof 
part above).
 
> I'm unsure about the RadioSync and NTP, best thing would be to contact them
> about it or read more on their site, I'm sure they get that question all the
> time. $199 for a modern timing receiver like that seems quite reasonable.

Indeed, that's what I was thinking. I'll drop them a line, but I'm a big 
fan of saving money and buying used where possible. That, and letting 
someone else take the first step and see if there's any problems. I've 
not heard of Beagle until today, so it'd be nice to see if anyone else 
has any experience with them.

> Another hurdle might be interference with the WWVB signal, but without
> having any equipment to test beforehand you are kind of diving in blind. A
> CDMA receiver you can test beforehand just seeing how good of a signal you
> get with your cell phone.

My CDMA phone gets full or almost full signal strength here, so there's 
no issues with that here. Still, the WWVB clock is significantly 
cheaper, and I'm perpetually tight on money.

-- 
Pete Stephenson
HeyPete.com




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