"Thierry" to answer direct see http://www.astrosurf.com/lombry/post.htm
wrote:

Does not exist ! But well dBW = 10 Log P, this is not the same excepting
reading from right to left, Hi!

OK, hi...

Your explanation is not one. refer my link for a correct explanations.

Taka a look at:

http://hyperphysics.phy-astr.gsu.edu.../sound/db.html

Anyway, how do you calculate the dBW on 20m with such a formula. Someone
calculated dBW on 10m, so we must be able to do the same at 20m...

This calculations aren't depend on frequency or wavelength.

Regards,

Ralf

--
Vy 73 es 55 de Ralf, DL2MRB
E-Mail:
Board: www.hamradioboard.de