FWIW for the 10MHz distribution amplifier I have been using LT1963 (40 uVrms in 10Hz to 100kHz) which is about 40x worse than the LT3042 spec of 0.8 uVrms in 10Hz to 100kHz. With decent op-amps I think the distribution-amp performance is limited by the op-amp noise and thermal noise in the resistors - I wouldn't expect the residual phase/amplitude noise to improve at all with a better LDO like the LT3042 - but ofcourse I haven't tried this :)
The LT3042 spot noise spec of 2nV/sqrt(Hz) corresponds to Johnson noise of a 250 Ohm resistor at room-temperature (if my spreadsheet-calc is right..) - so I guess if one has circuits that are already optimized/limited by supply voltage noise at that level then moving to the LT3042 makes sense. AW On Wed, Jul 10, 2019 at 12:02 PM Perry Sandeen via time-nuts < time-nuts@lists.febo.com> wrote: > Yo Bubba Dudes!, > The LT3042 seems to be a wonderful part. But having learned a long time > ago the it wasn't wise to gold plate a Yugo, so when are there diminishing > returns? > For example I have several HP 10811 oscillators. one is in a HP5335a > counter that I'd like to make as stable as reasonably possible. Another > HP10811 needs a power supply. Also several Lucent XO OCXO's. > So where is it practical to hack for better results and when do you use > some not -as -wonderful regulator chips that come in a much easier to use > dip package for a power supply upgrade? > Regards, > Perrier > > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts@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@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.