Re: [time-nuts] how many seconds out does GPS discipline being to improve Rubidium stability?

Surely you just loop it through two counters using a T-piece, with those counters set to high impedance input, then only terminate the final one? Peter On 12 February 2017 at 18:16, gkk gb wrote: > That is an interesting suggestion (thanks), and would indeed work

Re: [time-nuts] how many seconds out does GPS discipline being to improve Rubidium stability?

Hi How an ADEV floor do you expect to see on your devices? How short a Tau are you after. Depending on the answers to those questions, splitting things can be pretty easy or pretty hard. Isolating signals between multiple test sets is a bit of a pain if the splitting is not done with active

Re: [time-nuts] how many seconds out does GPS discipline being to improve Rubidium stability?

Hi You likely need to do this with something like a TimePod to get the resolution. Setting up three of them (or anything similar) is going to cost you way more than the Rb. If you have a 100 ps counter, you will get 1x10^-10 at 1 second for ADEV data. That will go to 1x10^-11 at 10 seconds

Re: [time-nuts] how many seconds out does GPS discipline being to improve Rubidium stability?

That is an interesting suggestion (thanks), and would indeed work for me if it is possible to split the DUT signal into 3 signals in a such a way that wouldn't affect measurements for ADEV, TDEV, MTIE. But I'm thinking anything active would introduce it's own noise into the signal and change

Re: [time-nuts] how many seconds out does GPS discipline being to improve Rubidium stability?

Could you do all three tests in parallel? One unit under test driving three counters. Each counter using a different reference signal, one on a OCXO, one on a rubidium, and one on a GPS disciplined oscillator. At each point in time during the test simply choose the one that gives the best

Re: [time-nuts] how many seconds out does GPS discipline being to improve Rubidium stability?

Hi Using ADEV as an example (the other stuff will have it’s own curves, but the result is the same): A typical Rb should have a stability at short tau that goes as 1/ square root(Tau). If you are at 2x10^-11 at 1 second, you will be at 2x10^-12 at 100 seconds and 2x10^-13 at 1,000 seconds.

Re: [time-nuts] how many seconds out does GPS discipline being to improve Rubidium stability?

Thanks Bob, I should clarify the MTIE measurement extends 10 seconds (the others are less time). Is it a reasonable question to ask if GPS is needed? Or are there other variables that are involved? Good point about the temperature stability, I hadn't considered that. Can I place in a

Re: [time-nuts] how many seconds out does GPS discipline being to improve Rubidium stability?

Hi Backing up a bit here. > On Feb 10, 2017, at 7:35 PM, gkk gb wrote: > > Hello experts, I need a Rubidium frequency reference for my company, and > wonder if I also need to GPS discipline it. > > > I characterize crystal-based OCXOs for ADEV, MTIE, and TDEV, and my

Re: [time-nuts] how many seconds out does GPS discipline being to improve Rubidium stability?

From: gkk gb Hello experts, I need a Rubidium frequency reference for my company, and wonder if I also need to GPS discipline it. I characterize crystal-based OCXOs for ADEV, MTIE, and TDEV, and my longest measurement time is 100,000 seconds (28 hours). []

[time-nuts] how many seconds out does GPS discipline being to improve Rubidium stability?

Hello experts, I need a Rubidium frequency reference for my company, and wonder if I also need to GPS discipline it. I characterize crystal-based OCXOs for ADEV, MTIE, and TDEV, and my longest measurement time is 100,000 seconds (28 hours). I'm looking at this graph from SRS for PRS10,