Yes, the oscilloscope PPS detection is really a FAQ and already discussed here. The use of a digital 'scope is recommended but the idea of dividing the PPS by 2 with a FF is useful and simple to implement, to detect if the PPS output is working or not. A more "sophisticated" one uses a monostable to stretch the 1uS pulse to 200mS to let it be solid visible. I use a CD4538 with 22nF and 10K to give a good pulse visibility.
On Mon, Aug 20, 2012 at 8:44 AM, Tom Miller <tmil...@skylinenet.net> wrote: > You can see it easily with any 50+ MHz analog scope that has a working DC > trigger function. > > If it is a 1 us pulse width TTL output or close, set the H sweep to 1 > us/div, The vertical to 1 volt/div, the triggering to normal, and the > trigger input to DC. Then adjust the trigger point to +1 volt. You should > see a sweep every second. If you turn up the intensity and dim the room > lighting, the pulse should be visible. > > If you are using a Tek scope and need help setting it up, just ping me and > I'll assist. Others on this list can also give good advise in seeing this > signal. > > > Regards, > Tom > > > > ----- Original Message ----- From: "Chris Albertson" < > albertson.ch...@gmail.com> > To: "Discussion of precise time and frequency measurement" < > time-nuts@febo.com> > Sent: Monday, August 20, 2012 1:52 AM > Subject: Re: [time-nuts] Trimble T Lassen 2 - > suitableantenna....advice.....questions > > > > On Sun, Aug 19, 2012 at 9:27 PM, Robert Darlington <rdarling...@gmail.com > >wrote: > > It's a pain to capture on any scope, but really easy to see with an >> LED across the output. it's not bright, but definitely easy to see on >> my tbolt. >> > > > That is true. One must have very good eyes to see a one microsecond pulse > that only happens one per second. Blink and you miss it. > > The LED might work but the "for sure" way is to send the PPS to a flip flop > so you can see the state change at 1Hz. Use a solderless bread board and > 5V power supply. > > > -- > > Chris Albertson > Redondo Beach, California > _______________________________________________ > 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. > _______________________________________________ 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.