[ntp:questions] Installing more stable oscillator?

Hal Murray hal-usenet at ip-64-139-1-69.sjc.megapath.net
Mon Jul 16 01:49:31 UTC 2007

>How good is the GPS 18 LVC as a time source? From what I can read, the
>leading edge of the PPS pulse is within 1 microsecond of UTC, which is
>certainly more than adequate for my needs, but it's always nice to do
>better if possible. :)

Mostly, it depends on how good your signal is.  The 1 microsecond
marketing number is useless if you don't have enough satellites
amd/or a stribg enough signal to decode them.

The GPS 18 is a modern GPS receiver.  It's reasonably good.
It's probably as good as any other low cost (aka consumer grade)
timing receiver.

Mine works inside my house.  I'm on the top/only floor and there
is no metal in the roof.  It only works if I get it up high.
That's probably because of the metal screening in the stucco walls.

Actually, being on the edge is good for debugging software.  It
generages lots of corner cases to test the software.  :)

You might try a modern GPS navigation unit in your apartment
and see if it gets a signal.  If you don't have one, maybe you
can borrow one fron a friemd.

I have an old hand-held unit that works fine outside but doesn't get
off the ground inside.

These are my opinions, not necessarily my employer's.  I hate spam.

More information about the questions mailing list