Question about a datasheet

[king.oslo]

Hello there,

Looking at the FEI rubidium datasheets. The one which Dave got has a short term drift of 10^-11/ day.

Here is the datasheet: http://www.freqelec.com/rb_osc_fe5680a.html

My question is, 10^-11 relative to what? 10MHz? 1Hz? Some other unit, or something else altogether?

Thanks,
Marius

[KJDS]

It's a ratio.

So as it's a 10MHz oscillator, then 10^7Hz * 10^-11 gives 10^-4 per day, or 0.1milliHz per day.