[time-nuts] 10 MHz -> 16 MHz

Pete Lancashire pete at petelancashire.com
Tue Oct 9 13:25:53 EDT 2018


I just wish the tapr would not discontinue things so fast it seems once you
see it mentioned it's discontinued

On Sun, Sep 30, 2018, 1:08 PM Bob kb8tq <kb8tq at n1k.org> wrote:

> Hi
>
> If (as originally specified) noise and jitter are not a big deal - there
> are a lot
> of chips out there like the ICS570. They are designed to do weird ratio
> frequency
> conversions so 10 to 12 or 10 to 16 are trivial for them. The Clockblock
> board was
> one way to get it all put together.
>
> Bob
>
> > On Sep 30, 2018, at 12:05 PM, Gerhard Hoffmann <dk4xp at arcor.de> wrote:
> >
> >
> > Am 30.09.2018 um 16:49 schrieb Attila Kinali:
> >
> >> The simplest way I can think of is the following:
> >> Use a 74LV8154 to divide the 10MHz down to 152.587890625Hz.
> >> Use the capture timer unit of the uC to measure the phase of the
> >> pulse. Use any kind of DAC (internal, external, PWM,...) to steer
> >> the 16MHz VCO. Depending on how fast the timer unit runs, this
> >> will give you something in the order of 10-200ns dead-band.
> >> By choosing the right frequency for the timer unit, one can
> >> get it to "dither" a bit and then use averaging.
> >>
> >> For lower jitter, use one half of a Nutt interpolator
> >> to get the timing difference between the 152Hz signal
> >> and the 16MHz (ie similar to what the SRS FS740 does).
> >> Use something akin Nick Sayer's time-to-amplitude converter
> >> for the fine measurement.
> >>
> >> Same works equally well for 12MHz.
> >>
> >>
> >
> > Wow. That's truly a Rube Goldberg design.
> >
> > There is a simpler way.  IDT ICS570. Digikey 800-1073-5-ND
> >
> > Solder time less than 10 minutes.
> > I had the 3V3-Version in the parts drawers, officially it takes the 5V
> > version to generate the 160 MHz, but the 3V3 version happened to work,
> too.
> > The difference between 120 and 160 MHz is just a GND wire on pin 6 (vs.
> open)
> >
> > Divide by 10 is left as an exercise.
> >
> > regards,
> > Gerhard
> >
> > (But then, some like to build and tune multiplier chains and mixers.)
> >
> >
> <Auswahl_008.png><times12.bmp><times16.bmp>_______________________________________________
> > time-nuts mailing list -- time-nuts at lists.febo.com
> > To unsubscribe, go to
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> > and follow the instructions there.
>
>
> _______________________________________________
> time-nuts mailing list -- time-nuts at lists.febo.com
> To unsubscribe, go to
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.
>


More information about the time-nuts mailing list