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Re: tiny board

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John Larkin wrote
>Our LMX2571s are working beautifully. That functionality would have
>been a rack full of gear, worth some good chunk of a magabuck, not
>that long ago. The jitter levels are amazing. 
>
>But the driver and the math were a real pain. We had to do the
>repeated-fraction thing to get the optimum (N/M)/K  to best hit a
>desired frequency. Brute force, it might be a week of computing.


In my case it is not all that critical,
divide 10 MHz Rubidium by 10 to 1 MHz,
divide 24 MHz or 25 MHz VCXO by 24 or 25 to get 1 MHz,
compare those in phase detector, steer the 25 MHz or 24 MHz VCXOs.
Output 24 or 25 MHz with Rubidium stability.
The 24 MHz will be multiplied in the LNB by 390 to 9360 MHz, and used to mix down the 10.4 GHz satellite signal.
The 25 MHz will be multiplied by 390 or 426 for use as LO for normal satellite reception.
That is the plan anyways.
Nothing happened today, was working in the garden...


>TI should supply some sample code. I can't imagine why they don't. It
>probably costs them sales.

Too many possibilities I guess..
But indeed some examples do help.
Could use that to verify my program.

If all else fails I was sort of thinking I can use a PIC (build in counters).
I have a quite accurate PIC frequency counter in a D connector:
 http://panteltje.com/panteltje/pic/freq_pic/

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tiny board John Larkin <jjlarkin@highlandtechnology.com> - 2018-10-09 20:22 -0700
  Re: tiny board <698839253X6D445TD@nospam.org> - 2018-10-10 06:30 +0000
    Re: tiny board tabbypurr@gmail.com - 2018-10-10 02:39 -0700
      Re: tiny board <698839253X6D445TD@nospam.org> - 2018-10-10 14:08 +0000
        Re: tiny board tabbypurr@gmail.com - 2018-10-10 08:34 -0700
    Re: tiny board DecadentLinuxUserNumeroUno@decadence.org - 2018-10-10 09:54 +0000
    Re: tiny board John Larkin <jjlarkin@highlandtechnology.com> - 2018-10-10 07:43 -0700
    Re: tiny board John Larkin <jjlarkin@highland_snip_technology.com> - 2018-10-10 11:12 -0700
      Re: tiny board <698839253X6D445TD@nospam.org> - 2018-10-10 19:12 +0000
        Re: tiny board John Larkin <jjlarkin@highland_snip_technology.com> - 2018-10-10 12:26 -0700
          Re: tiny board <698839253X6D445TD@nospam.org> - 2018-10-12 17:57 +0000
            Re: tiny board John Larkin <jjlarkin@highland_snip_technology.com> - 2018-10-12 12:55 -0700
              Re: tiny board <698839253X6D445TD@nospam.org> - 2018-10-13 06:59 +0000
                Re: tiny board John Larkin <jjlarkin@highlandtechnology.com> - 2018-10-13 08:54 -0700
                Re: tiny board <698839253X6D445TD@nospam.org> - 2018-10-13 18:19 +0000
  Re: tiny board George Herold <gherold@teachspin.com> - 2018-10-10 06:40 -0700
    Re: tiny board John Larkin <jjlarkin@highlandtechnology.com> - 2018-10-10 07:38 -0700

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