Frequency meter, has an input 10 MHz, better connect the output frequency standard, the counter inputs.
I am at home I have a GPS receiver (Trimble Thunderbolt) display (that shows the status of the receiver) and four 10 MHz output.
You can get STABILITY about 1x10-11, the more I would not count
Cesium clocks gain of about 1x10-13, 1x10-15's best
The most accurate clock is made ??in Poland pulsar clock about 1x10-16
http://en.wikipedia.org/wiki/Pulsar_clock
Cool the frequency standard although a little big
And you have some data about Thunderbolt stability?
(I have followed many Thunderbolts, HP Z3801's (what is far over TB stability) Good OCXO's and some Rb's. )
Please do real mesurement so that take continuously exaple 100 second averages from TB and and other source (example from other TB or other more short time stabile source) then compare these and show me statistics, example 1k pairs compared. After then tell me about what you mean with this:
You can get STABILITY about 1x10-11
How big peak-peak differencies you find in this test example between two TB and what you believe about stability after this imagined test. (I have not exatly this but I can quess with my other experience that you do not claim then even 1x10-10 or do you trust even 1x10-9 if take short time (example 1-100s) freq average.
Also it depends how you have set your TB. How accurate your antenna position really is, how you have adjusted optimal parameters for your individual TB (example discipline). Or do you run with factory defaults. Also there is big differencies between TB's. Some have more bad OCXO than others... some may have really bad and some may have acceptable good individual OCXO from Vectron if have good luck.
Long time average is good but is it stability?
What about if look what TB itself is thinking about itself, then, everybody have rigtht to his own religion withoud doubt ( smile ).
Then
in some publication:
"The widespread belief that pulsars are the best clocks in the universe is wrong, say physicists."
look attached image
Btw, If I want measure example frequancy. I hope I can do measurement in some minutes but I do not want wait very long time.
Poland pulsar clock about 1x10-16
But I do not want wait 100 year integration period. It is not so handy.
And it is good to think it is Allan variance... it do not mean...etc..