Hi Attila, I normally use the HP53132A in Frequency mode with the Timelab. The time interval mode, I know is more accurate but using the 1PPS as input you lost too much resolution. looking : http://www.timeok.it/wp/wp-content/uploads/2015/09/Timeok-Time-and-Frequency-House-Standard-v-2.1.pdf page 8, the noise floor using fmode is around 2.5E-12 at1 sec and 5.2E-14 at 1000Sec.
I would like to have around 100 time more resolution capability, in particular, in the 1-1000Sec range and short to long term stability measurement possibility. > How about implementing DMTD using ADCs? You could do something similar > to what the TimePod does using a dual >40Msps ADC to sample both signals > and feed that into a PC for processing. E.g. an AD9248-65 is available for > 40USD, add some 100-200USD for a suitable FPGA board. A small PCB to glue > the ADC and the FPGA board together, a little bit of software writing and > you are done ;-) > > Of course, this would not have the short term stability (aka low noise > floor) > of the TimePod, but beyond a second, it should give you good results. And > should be more than good enough to measure the ADEV of the devices we > usually > deal with. I am not a "Digital Person" and I cannot approach this kind of project I have not this knowledge, so I am looking some "analog" solution or any, ready to use, solution. Thank you for your help, Luciano www.timeok.it Message sent via Atmail Open - http://atmail.org/) On Wed 03/02/16 15:01 , Attila Kinali <att...@kinali.ch> wrote: > Ciao Luciano, > > On Wed, 03 Feb 2016 13:31:44 +0100 > tim...@timeok.it wrote: > > > Unfortunately it is very difficult to measure the Allan deviation levels > to > > E-14 and beyond. > > I have tried some solutions like Wavecrest and Dual mixer Time Interval > but > > with poor results: > > Do you think this is a general problem of comparing 10MHz standards > or just one of inadequate equipment? > > > Honestly I do not see at present practical solutions and reliable low > cost. > > How about implementing DMTD using ADCs? You could do something similar > to what the TimePod does using a dual >40Msps ADC to sample both signals > and feed that into a PC for processing. E.g. an AD9248-65 is available for > 40USD, add some 100-200USD for a suitable FPGA board. A small PCB to glue > the ADC and the FPGA board together, a little bit of software writing and > you are done ;-) > > Of course, this would not have the short term stability (aka low noise > floor) > of the TimePod, but beyond a second, it should give you good results. And > should be more than good enough to measure the ADEV of the devices we > usually > deal with. > > Attila Kinali > > -- > It is upon moral qualities that a society is ultimately founded. All > the prosperity and technological sophistication in the world is of no > use without that foundation. > -- Miss Matheson, The Diamond Age, Neil Stephenson > > > Message sent via Atmail Open - http://atmail.org/ _______________________________________________ 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.