WarrenS wrote: > It seems like you have given plenty of information for me to give you two > possible suggestion. > > Here is an almost no extra cost solution, (just takes care and helps if you > have done it before) > Take a pretty standard xtral osc with EFC, buffer its output real good, > give it good clean power from preferable its own regulator, > put a little insulted house around it so that it is not effected by direct > air flow and quick temperature changes, > Add a processor controlled PLL a driving a Dac to control it freq, > Update the PLL loop with the time beacon, (assuming it is good to better than > 1us) to correct the Phase offset error, > and it is pretty easy to get much better than 0.1 PPM with this. > I did about the same thing using the 1PPS of my GPS and could get around 1e-8 > accuracy. > The most important things are if using a cheap $5 osc like I was is to > isolate real well it from the effects of PS, > load and temperature, and have of low noise reference voltage to provide a > settable coarse freq tuning and use the Dac just for fine adj. > > Or of course you could just buy a better osc TCXO and save a lot of > development time, but that's not as much fun. > Depends how may you want to build, Anything below say 50 units the TCXO is > going to be the cheaper solution if time is money. > > ws > ********** > That is probably an unnecessarily expensive solution that doesn't address the fundamental problem of synchronising the RTC associated with each sensor to a common time base.
Bruce _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
