Hi If you are handling the sawtooth correctly, you should see no hanging bridges at all. My guess is that the spikes are coming from a problem in the sawtooth correction “stuff”. With no correction, you *will* see a spike as is rolls over. With a correction error, you would also see a spike.
Bob > On Nov 10, 2020, at 11:37 AM, Joe & Gisela Noci <[email protected]> wrote: > > Hi Bob, > Yes, I am - I use a Dallus digital delay line in series with the GPS 1pps > and program the delay line each second with the GPS delay estimate in the > GPS NAV message. > It works really well, jitter on the 1pps pulse is hugely reduced, but one > side effect is that those 'hanging bridges' can become severely extended in > time. > I can by pushbutton selection bypass the delay line, ie, no sawtooth > correction - since I do not have a reference frequency source, I cannot say > if it is better or worse. > However, the logged values output from the time-digital convertor still > shows the spikes either way- I still suspect the spikes are conversion > artifacts from digital noise in the box.. > Being green on the science of this I packed to much 'stuff' into the > enclosure and there are DC-DC converters for power, Nucleo processor > running at 140MHz, a NEXTION touch screen LCD, which > I am discovering is very noisy, etc....It is difficult to target any > solution at the moment as I believe there are too many areas that are > marginal - I need to clean it up! > Joe > > On Tue, Nov 10, 2020 at 6:24 PM Bob kb8tq <[email protected]> wrote: > >> Hi >> >> Are you using sawtooth correction? >> >> Bob >> >>> On Nov 10, 2020, at 8:55 AM, Joe & Gisela Noci <[email protected]> wrote: >>> >>> Hi everyone, >>> Still playing with my GPSDO..The Rubidium source I was hoping to have the >>> loan off did not work out, so still in the dark. I have sort of convinced >>> myself to procure a reasonable 'proven' source, Rubidium or whatever, but >>> that >>> seems to be more easily decided than done..Or at least so if the money >>> available is not astronomical... Also complicated by the difficulties >>> getting the goods here to Namibia! >>> >>> Anyway, I am still unhappy with my analogue time-to-digital conversion - >> I >>> do see the odd spike in the logged data and have been unable to find why >> - >>> have applied lots of filtering of supplies, used a separate A/D >> convertor ( >>> as opposed to the convertor internal to the STM Processor) with own dc >>> regulated supply, own clean A/D Reference voltage ( 1ppm device). etc... >>> >>> Does not mean implementing a digital method will get rid of the spikes, >> so >>> I am still chasing that till I understand, but to that end: >>> I found this device and am keen to get the dev kit and try it out : >>> >> https://www.sciosense.com/products/time-to-digital-converters/development-kit-for-as6500/ >>> >>> Has anyone perhaps played with it? Would be interested to know more about >>> it if so.. >>> Regards >>> Joe >>> V51JN / ZS6JGN >>> >>> On Wed, Oct 28, 2020 at 7:08 PM Alberto di Bene <[email protected]> wrote: >>> >>>> On 2020-10-28 2:29, jimlux wrote: >>>>> I'm still agitating for alien deviation - Microsoft offers it as a >>>>> suggestion, but not Allan, so it must be true. >>>> >>>> :-):-):-) >>>> >>>> Thanks Tom and Jim for the explanations. All clear now. >>>> >>>> 73 Alberto I2PHD >>>> >>>> >>>> >>>> _______________________________________________ >>>> time-nuts mailing list -- [email protected] >>>> To unsubscribe, go to >>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>>> and follow the instructions there. >>>> >>> _______________________________________________ >>> time-nuts mailing list -- [email protected] >>> To unsubscribe, go to >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >>> and follow the instructions there. >> >> >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >> and follow the instructions there. >> > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
