Why not run an experiment? Connect a serial and a USB GPS-18 to the
same NTP server. and run BOTH ref clocks at the same time. Let it
run for a day or so them please, post the results for NTPQ here.
Windows is a poor platform for timing. You are best off with Linux or
BSD UNIX and a real
Note that MAX232 type chips add jitter. The charge pumps make substrate noise
and that leaks into the receivers/transmitters.
I like that addafruit solution.
Note the beagle XM has a bug in the USB that RCNelson fixed. I have managed to
get it in opensuse, but can't say for sure yet if it is
On Mon, May 13, 2013 at 7:52 PM, li...@lazygranch.com wrote:
Note that MAX232 type chips add jitter. The charge pumps make substrate noise
and that leaks into the receivers/transmitters.
How much noise or jitter? Has anyone measured the effect? Is it at
the nano or micro second level? It
