[time-nuts] New topics (was Re: He is a Time-Nut Troublemaker....)

[Lux, James P]

On 12/24/08 6:04 AM, "Didier" <didier at cox.net> wrote:

>> -----Original Message-----
>> On Behalf Of Magnus Danielson
>>
>>
>
> Specifically, John was suggesting adding the two 5MHz signals, instead of
> locking them, that's why I added "statistically independent".
>
>>> So as when you average n signals, the noise and drift are
>>> reduced by sq.rt of n, in this case, 1.4, or about 2dB
>>> (if I am correct), a modest improvement.
>>
>> Square root of 2 is about 1,414 or about 3,01 dB.
>
> I am always confused when considering noise, is it 10*log(p1/p0) or
> 20*log(p1/p0)?


If you're talking noise POWER (or variance..) 10 log10(p1/p0)
If you're talking noise voltage (or standard deviations) 20 log10(v1/vo)