Thank you both for responses. I wanted to see how far the signal would go with open hallway and with a first set of offices with drywall measuring at 5Ghz from 29, 25, 20, 15, 10, 5 & 1. Please see PDF for details. I'm not sure I understand the power chosen vs. output, but I saw something about having to wait to see the adjustment, as well. I changed the power, took note of the change, and walked.
Echoing what super knowledgeable ww mentioned, this is likely to do with the regulatory domain.
Each country has a specific maximum power that it allows on its soil, for example for Europe you are likely looking at 20/23dBm (depending if you are on 2.4 or 5 GHz) maximum ( source ).
If we assume we have a brand new MR46 broadcasting on channel 136 (5GHz), we can look at the datasheet , see that the antenna gain for the 5GHz radio is at 6dBi, factor in 3 dB for beamforming and we can then reverse the EIRP formula:
Maximum transmit power = 23 dBm (maximum EIRP) - 6 dBi (antenna gain) - 3 dB (beamforming) + 0 dB (pretending for a second we don't live in the real world where there is cable loss)
Which results in 14 dBm of maximum transmit power achievable in Europe on the 5GHz range.
Dashboard would still allow you to target the highest transmit power possible (30), but it will then do all the calculations and work its magic for you to ensure you remain compliant to the legal regulations for wireless transmission.
Hope this helps!
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