On 4/13/20 9:28 PM, saipan59 (Pete) wrote:
Thanks for your comments! To clarify a bit:?
The module has both a freq output, and a 1 PPS output. I know how to
program the freq output (it defaults to 10 MHz, but I can change it to
all sorts of values). It has a small connector for an active antenna.
Some years ago, I bought a mag-mount "turtle" with a few feet of cable,
from a Chinese vendor. I hooked it up to a little MCU board to
send/receive serial data. The module has a couple of LEDs that indicate
the status of GPS lock and such (it even does a blinking pattern to show
how many satellites are acquired). All seems to work.
But what I'm asking is: What is the "quality" of the freq output from
this thing likely to be? The NavSync docs don't seem to address this
aspect, other than to compare it to a Cesium source and such - it
doesn't describe specs such as jitter, which I (think) understand is a
key measurement of short-term performance. The docs do say that the 1
PPS edge is +/- 30 nS from UTC.
Another way to phrase the question: What does the OP's "Leo Bodnar" box
do that is "better", when it comes to "signal quality" for a basic 10
MHz reference??
A third way to phrase the question: If I use this module as a reference
for my HP5345A counter, is it "better" than the internal reference?
The long-term stability is likely to be very good. But without
knowing more about the architecture of the device, anything else is hard
to say. It's probably a PLL-based frequency synthesizer, so, phase
noise...but how much and where? You can measure it, but not without
something "better" than your board is likely to be.
You are standing on the precipice of becoming a Time Nut. Fair
warning. ;)
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
Dave McGuire