For a radio BFO you want something with low phase noise (low jitter). The SI5351 is not designed for that, and it's jitter spec is 70 ps, which is pretty noisy. It even has a spread spectrum mode that would be even worse. They do have other parts designed for low jitter (< 1ps). Leo Bodnar's GPSDOs with variable output clock frequencies are based on those chips and they provide low phase noise, certainly enough for a radio.
Regards, Mark On Sun, Sep 16, 2018 at 10:22 AM, Chris Waldrup <[email protected]> wrote: > How about using a ProgRock on Hans Summers QRP Labs website? This is a > programmable crystal replacement. > > Chris > KD4PBJ > > > On Sep 14, 2018, at 8:06 PM, paul swed <[email protected]> wrote: > > > > The beauty of a $2 arduino and a drop of code snitched from Engineer > google. > > OK enough of that back to the thread. > > Regards > > Paul > > WB8TSL > > > >> On Fri, Sep 14, 2018 at 8:04 PM, Mike Feher <[email protected]> wrote: > >> > >> Not when I built them in the late 60's and early 70's. All discrete. 73 > - > >> Mike > >> > >> > >> > >> Mike B. Feher, N4FS > >> > >> 89 Arnold Blvd. > >> > >> Howell NJ 07731 > >> > >> 848-245-9115 > >> > >> > >> > >> -----Original Message----- > >> From: time-nuts <[email protected]> On Behalf Of Richard > >> (Rick) Karlquist > >> Sent: Friday, September 14, 2018 7:15 PM > >> To: Discussion of precise time and frequency measurement > >> <[email protected]>; ed breya <[email protected]> > >> Subject: Re: [time-nuts] Programmable clock for BFO use....noise > >> > >> > >> > >> > >>> Finally, of course, you can use DDS. This is nearly an ideal case for > >> > >> > >> > >> The trouble with a DDS is that you need a microcontroller with software > >> just > >> to baby sit the thing. > >> > >> > >> > >> Rick N6RK > >> > >> > >> > >> _______________________________________________ > >> > >> time-nuts mailing list -- <mailto:[email protected]> > >> [email protected] To unsubscribe, go to > >> <http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com> > >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >> > >> and follow the instructions there. > >> > >> _______________________________________________ > >> time-nuts mailing list -- [email protected] > >> To unsubscribe, go to http://lists.febo.com/mailman/ > >> listinfo/time-nuts_lists.febo.com > >> and follow the instructions there. > > _______________________________________________ > > time-nuts mailing list -- [email protected] > > To unsubscribe, go to http://lists.febo.com/mailman/ > listinfo/time-nuts_lists.febo.com > > and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to http://lists.febo.com/mailman/ > listinfo/time-nuts_lists.febo.com > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
