For a good look at the rules go read my first post here put the link back together.
FCC Rules Part 15 Section 247 limits Effective Isotropic Radiated Power (EIRP) with an omnidirectional antenna to 36dBm. Period. You can combine a 30dBm transmitter to a 6dBi antenna, or a 18dBm transmitter to a 18dBi antenna, but you cannot exceed 36dBm EIRP when using an omnidirectional antenna.
There is an allowance for a 1dBm amplifier reduction with a 3dBi of antenna gain only when using a directional antenna, in a point-to-point configuration.. In that case the maximum allowed is a 22dBm (160 mW) transmitter used in conjunction with a 30dBi directional antenna for an EIRP of 160.0W.
Thanks for the clarification on the rules, the cute dBm to watt conversion table did not have an exact reading and never mentioned a directional antenna. So I am 4.2 dB over allowable maximum for a one to one with an omni directional antenna. It is a good thing I am not in the USA to face the ire of the FCC. Also since our transmitter is in a boat we are at times more than 1/2 mile away from any AP's. Anyway, I am not apologizing for solving my own problems with distance on a constantly moving object.
Seriously, it just proves you have to read the source information. In this case the FCC rules are all available online.
Hi guys, I need help to choose an antenna.
At first I tried with the home made-mc giver staff but with really bad results, so I choose to buy a ready made antenna but don't know which one choose!
Don't think I really need too much distance but seeing those models with impressive distance range makes me desire them!
So now I'm stacked and can't choose which one between those
2.4GHz PANEL 20 dBi Antenna
5.8G GRID 27dBi+Lightning Protector-RTNCP-400-15m
Or this one:
+30dBm NextG USB-Yagi High Power WiFi Antenna
This looks great, better performance than the others, easy to use, a cheaper price but I don't like the integrated dongle, I like the idea of using any pci card I want with the other.
So any opinion?