Any of you can clear a doubt about what antenna gain value dB (for external antenna configuration)
I should define in the field where the range is if (-128 to 128) I have a 1242 AP ,I'm using an antenna 1728 (5.2 dBi)
and I would like to have the máximun EIRP.
Setting the gain there will not change your EIRP. That is used for information purposes if you have a WLSE. So to get the most out of your setup, you would set your TX power to 100mW (20dBm). You maximum EIRP is your TX in dBm plus your antenna gain minus connectors, cable and or lightning protection.