Hi Bryan, No ! Assuming you mean R1/R2/C1/C2 of the Miller schematic, those values are already set for the comparison frequency (10KHz) of the PLL phase comparator (U2). Bill....WB6BNQ Bryan _ wrote: >Hello: >I have been following the Jim Miller simple GSDO build project at http://www.jrmiller.demon.co.uk/projects/ministd/frqstd0.htm I have a few OCXO's kicking around, but wondering what would the appropriate components be for for R1,R2, C1, C2 to provide the PLL filter. I assume the PLL filter needs to be designed to accommodate a specific oscillator specifications, or maybe it doesn't really matter and can use the default values in the schematic?. >Was also considering using a picdiv instead of the 2- 74HC390, not sure if that would be an advantage or disadvantage in terms of operating performance? >Cheers > >_______________________________________________ >time-nuts mailing list -- time-nuts@febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. > > >

Thank you for the reply. Yes, R1/R2/C1/C2 is what I was referencing. I was not sure as the values in the schematic are referenced when using the C-MAC (now RAKON) VCXO. Further into the material the author switched to a Isotemp 134-10 OCXO and used a DC amplifier to compensate for the 0-8v for the EFC, but stated that R2 and C2 are not needed when using this OCXO. Not sure why they are omitted, is it because of the DC amplifier or because of different specs of the OCXO? http://www.jrmiller.demon.co.uk/projects/ministd/dcamp.gif -=Bryan=- > Date: Mon, 12 Sep 2016 01:25:53 -0700 > From: wb6bnq@cox.net > To: time-nuts@febo.com > Subject: Re: [time-nuts] Jim Miller simple GPSDO > > Hi Bryan, > > No ! Assuming you mean R1/R2/C1/C2 of the Miller schematic, those > values are already set for the comparison frequency (10KHz) of the PLL > phase comparator (U2). > > Bill....WB6BNQ > > > Bryan _ wrote: > > >Hello: > >I have been following the Jim Miller simple GSDO build project at http://www.jrmiller.demon.co.uk/projects/ministd/frqstd0.htm I have a few OCXO's kicking around, but wondering what would the appropriate components be for for R1,R2, C1, C2 to provide the PLL filter. I assume the PLL filter needs to be designed to accommodate a specific oscillator specifications, or maybe it doesn't really matter and can use the default values in the schematic?. > >Was also considering using a picdiv instead of the 2- 74HC390, not sure if that would be an advantage or disadvantage in terms of operating performance? > >Cheers > > > >_______________________________________________ > >time-nuts mailing list -- time-nuts@febo.com > >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > >and follow the instructions there. > > > > > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there.