OK, I'll follow the Enrico Rubiola/TSC5120 literature. On Tue, Apr 17, 2012 at 1:39 PM, Bob Camp <li...@rtty.us> wrote:
> Hi > > My *guess* is that your 1Hz data may be as much from ambient changes as > from the op amps themselves. No data to back that up on these specific > parts, just a guess. > > Bob > > On Apr 17, 2012, at 7:28 AM, Bruce Griffiths wrote: > > > Not yet, I just used the pair of TI evaluation boards which I obtained > for another project. > > > > I intend to mount the various components (splitters, 180 degree hybrids > etc) on a thick aluminium plate to improve the mechanical and thermal > stability of the system. > > > > Bruce > > > > Bob Camp wrote: > >> Hi > >> > >> Did you do any temperature stabilization on the op amps? > >> > >> Bob > >> > >> On Apr 17, 2012, at 5:25 AM, Bruce Griffiths wrote: > >> > >> > >>> Subsequent measurements using an improved technique has allowed the > true flicker phase noise characteristics of a pair of OPA653 opamps to be > determined. > >>> > >>> Opamp > >>> Gain 1x (6db folled by 6 db attenuator consisting of a 50 ohm > resistor in series with the output of the opamp and the 50 ohm load > resistor) > >>> Signal input level: + 10dBm > >>> > >>> OFFSET Opamp PN (dBc/Hz) Measurement system PN (dBc/Hz) > >>> > >>> 1 -148 -161 > >>> > >>> 10 -161 -172 > >>> > >>> 100 -164 -177 > >>> > >>> 1000 -164 -179 > >>> > >>> Source: 10MHz low phase noise OCXO removed from a Thunderbolt > amplified by a QBH9816 amplifier. > >>> > >>> Conclusion: FET opamp PN in the flicker region can be quite low > despite its somewhat higher baseband flicker noise than that of some > bipolar input opamps. > >>> > >>> Bruce > >>> > >>> _______________________________________________ > >>> 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. > >> > >> > > > > > > _______________________________________________ > > 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. > _______________________________________________ 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.