Re: Επαναφορά init script / Greeklish στη λίστα

[V13 <v13@v13.gr>]

On Tuesday 06 October 2009, Christos Ricudis wrote:
> V13 wrote:
> > On Tuesday 06 October 2009, V13 wrote:
> >>  ερωτήσεις. Το να αγνοηθούν μερικά mail το πολύ-πολύ να μειώσει το SNR.
> >
> > Αυξήσει
> 
> Ναι, αλλα κατα ποσα dB?

An to ypologisa sosta einai ~ 3db (=10*log(2)) an kopei to noise sto miso:

SNRold = S / Nold
SNRnew = S / Nnew
Nold = 2 * Nnew

=> SNRnew = 2 * SNRold

Δdb = db1 - db0
db0 = 10 * log(SNRold)
db1 = 10 * log(SNRnew)
    = 10 * log(SNRold*2)
    = db0 + 10 * log(2)

Δdb = 10 * log(2)
    = 3.01029995664 kai kati psila

.. kapoios apo ee.auth.gr h kati sxetiko as me diorthosei :-)

<<V13>>