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<p>Glenn,</p>
<p>Yes this would be a software solution, except that at 2M, you
would need a pretty robust micro to</p>
<p>accept that high a frequency in its counter input. Probably a
prescaler chip would be required.</p>
<p>I know some of the PIC chips could take up to 60Mhz input.</p>
<p>73</p>
<p>Glen K4KV</p>
<p><br>
</p>
<br>
<div class="moz-cite-prefix">On 6/13/2018 02:13, Glenn Thomas wrote:<br>
</div>
<blockquote type="cite"
cite="mid:727fe6a7-98f4-21a1-64f6-d759d8095565@gbis.com">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<font face="Comic Sans MS">Hi Glen (1 n!)<br>
<br>
One approach is to use the 1 pps to gate a counter that's
counting the oscillator frequency. The oscillator can then be
adjusted based on the difference between the measured freq and
the desired freq. The 1 pps from a GPS can be accurate to <1
ns, which is better than 1 Hz in 1000 MHz. The internal GPS
clock period is known to the GPS software to within 0.1 ns -
it's part of the navigation solution. Whether the output 1 pps
is controlled to this level of accuracy or not is a design
detail in your GPS box!<br>
<br>
73 de Glenn (2 n) WB6W<br>
</font><br>
<div class="moz-cite-prefix">On 6/12/2018 5:50 PM, K4KV wrote:<br>
</div>
<blockquote type="cite"
cite="mid:d6b797d6-08cb-63b2-6ae7-0d9060beee00@k4kv.com">*****
High Performance Software Defined Radio Discussion List ***** <br>
<br>
Hello, <br>
<br>
I have just ordered a qrp labs beacon kit with a gps unit that
has a 1pps output. <br>
<br>
I have been told that they use software to 'read' the gps and
then automatically <br>
<br>
correct the Siliconix programmable oscillator. Granted, this
takes quite a while to <br>
<br>
get it right. <br>
<br>
But still, I cannot see how it can be very accurate compared to
a 10Mhz GPS output <br>
<br>
reference. <br>
<br>
These 1pps output modules are quite inexpensive. <br>
<br>
Can someone point me to a white paper where someone describes
how to use software <br>
<br>
to correct a programmable oscillator using a 1pps system? <br>
<br>
73 <br>
<br>
Glen K4KV <br>
<br>
<br>
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<br>
<pre class="moz-signature" cols="72">--
"i" before "e" except after "c", or when sounded as "a" as in neighbor and weigh.
This rule is “counterfeit”. General spelling rules “forfeit” generality.
They are “foreign”, being not “either” or “neither”, possibly the result of some
“leisure” activity of a “sovereign heir” who, lacking “height”, is studying,
without “conscience, inefficient glacier science”. It’s not as nutritious
as "protein". It's just plain old "weird"
Is this example “sufficient”?
</pre>
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