attila@kinali.ch said: > There have been a couple of discussions about doing GPSDOs using only analog > components in the past. People fare more knowledgable than me have commented > there on what the challenges would be and how to solve them. So I recommend > to go through the archives and look for those discussions. They might be a > little bit hidden, though. I think the main problem is how to build a filter with a time constant of many seconds. The better your OCXO the longer the time span you can integrate over. 100s of seconds isn't an unreasonable target. There may be other problems. -- These are my opinions. I hate spam.

Hi As others have pointed out, a control loop at 100 seconds is more a gain spec than an R/C time constant spec. The real issue is that you should have an integrator on the loop and that *is* an R/C sort of thing. It’s also likely to have a much longer time constant than the magic number for the loop. Bob > On Mar 22, 2017, at 2:24 PM, Hal Murray <hmurray@megapathdsl.net> wrote: > > > attila@kinali.ch said: >> There have been a couple of discussions about doing GPSDOs using only analog >> components in the past. People fare more knowledgable than me have commented >> there on what the challenges would be and how to solve them. So I recommend >> to go through the archives and look for those discussions. They might be a >> little bit hidden, though. > > I think the main problem is how to build a filter with a time constant of > many seconds. The better your OCXO the longer the time span you can > integrate over. 100s of seconds isn't an unreasonable target. > > There may be other problems. > > > -- > These are my opinions. I hate spam. > > > > _______________________________________________ > 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.