Erik As a future time-nut you are on a great starter path. The very best results start out as globs of wires, tape, and widgets all tied together. There can be issues when you start to get very accurate. With respect to the clock, I don't think its ever going back to the livingroom. But I would highly expect it to drift in relationship to gps or Rb. I would expect at least 2 behaviors temperature through the day and then the longer term drift. One trick thats used to get results faster is to sniff out the 32 KHz oscillator and measure that. Since its about 64,000 times faster than the impulse. As you learn and become more accurate with better data you see new behaviors that you start to look into. At that point I think you are hooked as a time-nut. Good luck and share what your doing. Regards Paul WB8TSL
On Fri, Apr 22, 2022 at 1:32 PM Erik Kaashoek <e...@kaashoek.com> wrote: > Today I did a first real measurement of our living room quartz clock > using a prototype of a GPS/timer/counter. > See photo of the test setup: > http://athome.kaashoek.com/time-nuts/clock.JPG > The GPS/timer/counter has a build in GPS with PPS to measure and correct > its internal reference. Nothing special > On the display you can see from left to right at the top settings > related to the three sources of time/frequency: > - Input A, nothing connected, waiting for input > - Input B, where the quartz clock is connected to (DC, 0.8 V trigger > level, 1.8s gate time). > - GPS status > Below the top row you have 3 (can be 1 to 6) numerical data lines > showing data derived from the inputs mentioned above > - Frequency of the quartz clock. As the clock outputs alternating wide > and narrow pulses to drive the coil I had to set the trigger level to > only catch the wide pulse so the frequency is 0.5 Hz > - Instantaneous GPS PPS frequency > - Averaged GPS PPS frequency > And below the data lines you have a graph area where you can graph any > of the data lines. In this case a plot of the measured frequency of the > quartz is shown > The input B is directly connected to the coil of the quartz, no other > signal conditioning is used. > Using the above setup the ADEV of the quartz clock was measured, see: > http://athome.kaashoek.com/time-nuts/Quartz%20clock.png > The measurement of the setup above was labeled with "tinyCount" > I also measured the same quartz clock using a U6200A and a Rb reference, > this is labeled with U6200A > These two measurements seem to be in broad agreement but this may be > just me being overly optimistic. > For people that have worked on atomic clocks or GPS systems this may > look like childsplay and it indeed not very impressive but I am happy > with what I have accomplished. > Erik. > > > > > > > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send > an email to time-nuts-le...@lists.febo.com > To unsubscribe, go to and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-le...@lists.febo.com To unsubscribe, go to and follow the instructions there.