As I mentioned previously, in some 3-day tests one particular FTS1050A (FTS1050AB7 in the plots) performs well (bottom curves) and in other tests it performs somwhat poorly (upper curves). All the comparators in this MADEV plot perform similarly, so there is no obvious reason why there is split into good and bad cases. I have never before seen this behavior. I will open up the case and do some power supply testing. Another suggestion a reader made was that it could be a solder problem in the oscillator assembly. The control circuits may also have a problem. I will pull out all the PC boards, clean off the edge connector contacts, and reseat them. Jim

Have you looked at a phase plot? You may learn a lot... Mike -----Original Message----- From: Jim Schatzman via time-nuts <time-nuts@lists.febo.com> Sent: Friday, April 28, 2023 10:30 PM To: time-nuts@lists.febo.com Cc: Jim Schatzman <james.schatzman@futurelabusa.com> Subject: [time-nuts] FTS1050A data As I mentioned previously, in some 3-day tests one particular FTS1050A (FTS1050AB7 in the plots) performs well (bottom curves) and in other tests it performs somwhat poorly (upper curves). All the comparators in this MADEV plot perform similarly, so there is no obvious reason why there is split into good and bad cases. I have never before seen this behavior. I will open up the case and do some power supply testing. Another suggestion a reader made was that it could be a solder problem in the oscillator assembly. The control circuits may also have a problem. I will pull out all the PC boards, clean off the edge connector contacts, and reseat them. Jim

Hi Typically with this sort of stuff, one starts looking at the raw phase data to see what’s happening. Things like xDEV data are a bit “high level” when you start to troubleshoot this or that. Abrupt steps suggest one thing, gradual changes might suggest something else. Goes up and then comes back hints at a different sort of issue than “always goes the same way”. Once you have a guess, there could be reason to monitor current drain or even output level to narrow things down. Bob > On Apr 28, 2023, at 10:29 PM, Jim Schatzman via time-nuts <time-nuts@lists.febo.com> wrote: > > As I mentioned previously, in some 3-day tests one particular FTS1050A (FTS1050AB7 in the plots) performs well (bottom curves) and in other tests it performs somwhat poorly (upper curves). All the comparators in this MADEV plot perform similarly, so there is no obvious reason why there is split into good and bad cases. I have never before seen this behavior. > > I will open up the case and do some power supply testing. Another suggestion a reader made was that it could be a solder problem in the oscillator assembly. The control circuits may also have a problem. I will pull out all the PC boards, clean off the edge connector contacts, and reseat them. > > Jim<AB7.png>_______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe send an email to time-nuts-leave@lists.febo.com

Bob- Thanks for the tips. The raw phase data for the cases with not-so-good MADEV have more abrupt slope/frequency changes. I will investigate over the next few days. At 11:26 AM 4/29/2023, Bob Camp wrote: >Hi > >Typically with this sort of stuff, one starts looking at the raw phase data >to see what’s happening. Things like xDEV data are a bit “high level” when >you start to troubleshoot this or that. > >Abrupt steps suggest one thing, gradual changes might suggest something else. >Goes up and then comes back hints at a different sort of issue than “always goes >the same way”. > >Once you have a guess, there could be reason to monitor current drain or even >output level to narrow things down. > >Bob > >> On Apr 28, 2023, at 10:29 PM, Jim Schatzman via time-nuts <time-nuts@lists.febo.com> wrote: >> >> As I mentioned previously, in some 3-day tests one particular FTS1050A (FTS1050AB7 in the plots) performs well (bottom curves) and in other tests it performs somwhat poorly (upper curves). All the comparators in this MADEV plot perform similarly, so there is no obvious reason why there is split into good and bad cases. I have never before seen this behavior. >> >> I will open up the case and do some power supply testing. Another suggestion a reader made was that it could be a solder problem in the oscillator assembly. The control circuits may also have a problem. I will pull out all the PC boards, clean off the edge connector contacts, and reseat them. >> >> Jim<AB7.png>_______________________________________________ >> time-nuts mailing list -- time-nuts@lists.febo.com >> To unsubscribe send an email to time-nuts-leave@lists.febo.com