Hi
> On Sep 28, 2017, at 6:59 PM, Mark Sims <hol...@hotmail.com> wrote: > > I suspect that it is either temperature related (the funkiness starts around > when the temperature reaches a minimum) or related to the way the > disciplining parameters are hacked to get the extended time constant. Like it or not, most of these devices were made back a while ago. The CPU’s used were not the ones we have today. the code was tested over the “expected range” of values. Most (but not all) of the control loop code was done as integer math. With limited RAM, tossing everything into 64 or 128 bit integers was not an option. In some cases 32 bit int’s were at a premium. Multiply this by that, that, and that. Then divide by something, and something else. … hmmm…. a few bits just went missing. Could you reorder and fiddle to fix some of this? Sure, that’s where we get back to the expected range stuff. Even if it’s not in the “main loop”, GPSDO code is full of checks for this or that. Like the main math, they are scaled and tested for the normal range of parameters. Not all of them spurt error messages when they get involved. Some just bump this or that and move on. Lots of possibilities …. Bob > Try setting up for say a 10,000 second time constant and see how things > change. > _______________________________________________ > 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.
