[ntp:questions] Do I have a lock to my NMEA GPS?

Terje Mathisen "terje.mathisen at tmsw.no" at ntp.org
Fri Nov 9 21:05:46 UTC 2012

Ralph Aichinger wrote:
> David Woolley <david at ex.djwhome.demon.invalid> wrote:
>> You have at least a partial lock.  Only time will tell if it is going to
>> stay locked.  Your frequency quality wil not be good and your time
>> quality will be worse!
> Thanks a lot, I just wanted to be sure. The eTrex sends lots of useless
> crap on the NMEA output, the serial converter is probably a bad idea
> for more than testing, and I am stress testing my system (Raspberry Pi)
> at the moment by playing MP3s and sending stuff over another serial
> adapter. So the high jitter is to be expected.
> Now I just have to decide between the Adafruit GPS and the Sure
> Electronics board. Probably the shipping costs will be most
> relevant.

I really like the Sure board, I've installed 3 of them now, all with the 
two patch cables David T documents on his web site.

I don't know exactly how much power it needs, but since it runs easily 
on USB power, it has to use less than 500 mA @ 5V (2.5W), and probably 
significantly less.


- <Terje.Mathisen at tmsw.no>
"almost all programming can be viewed as an exercise in caching"

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