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On 6/26/19 10:11, Paul Theodoropoulos wrote:<br>
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cite="mid:28a1fd4c-ebdc-0c07-bf95-bc7166c2230b@anastrophe.com">
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On 6/26/19 10:03, Gary E. Miller wrote:<br>
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cite="mid:20190626100330.589b4d93@rellim.com">
<pre class="moz-quote-pre" wrap="">Yo Paul!
On Wed, 26 Jun 2019 08:36:04 -0700
Paul Theodoropoulos <a class="moz-txt-link-rfc2396E" href="mailto:paul@anastrophe.com" moz-do-not-send="true"><paul@anastrophe.com></a> wrote:
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<pre class="moz-quote-pre" wrap="">refclock shm unit 1 refid PPS minpoll 0 maxpoll 0 flag4 1 prefer
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<pre class="moz-quote-pre" wrap="">Depending on many things, I find that poll 2 or 3 is often the best
choice. One may give you better jitter and another better frequency
stability.
ntpviz will help you see the differences. I've done consecutive tests
stepping through the possible poll intervals.
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<br>
For sure - I'll take a poke at it.<br>
<br>
So little time, so much experimenting to do!<br>
<br>
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wow, fascinating - I set my c-ntpsec PPS min/maxpoll to 2. The RMS
time jitter rose a fairly significant amount, from hovering around
0.6<span style="color: rgb(0, 0, 0); font-family: "Exo 2";
font-size: medium; font-style: normal; font-variant-ligatures:
normal; font-variant-caps: normal; font-weight: 400;
letter-spacing: normal; orphans: 2; text-align: right;
text-indent: 0px; text-transform: none; white-space: normal;
widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px;
text-decoration-style: initial; text-decoration-color: initial;
display: inline !important; float: none;">µs</span> to now 1.0<span
style="color: rgb(0, 0, 0); font-family: "Exo 2";
font-size: medium; font-style: normal; font-variant-ligatures:
normal; font-variant-caps: normal; font-weight: 400;
letter-spacing: normal; orphans: 2; text-align: right;
text-indent: 0px; text-transform: none; white-space: normal;
widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px;
text-decoration-style: initial; text-decoration-color: initial;
display: inline !important; float: none;">µs</span> -- while the
RMS frequency jitter plummeted from hovering around 4ppb down to,
well, barely discernably above 0ppb on the graph. <br>
<br>
eh, saying it just doesn't tell the story - <br>
<br>
Time jitter: <a class="moz-txt-link-freetext" href="https://i.imgur.com/jNlaAAj.png">https://i.imgur.com/jNlaAAj.png</a><br>
<br>
Frequency jitter: <a class="moz-txt-link-freetext" href="https://i.imgur.com/wAF2nu9.png">https://i.imgur.com/wAF2nu9.png</a><br>
<br>
<br>
<pre class="moz-signature" cols="72">--
Paul Theodoropoulos
<a class="moz-txt-link-abbreviated" href="http://www.anastrophe.com">www.anastrophe.com</a></pre>
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