Calculate equivalent isotropically radiated power easily on the go:
EIRP calculator let you calculate the effective transmission power with a given combination of radio transmitter and antenna.
Equivalent isotropically radiated power (EIRP) or, alternatively, effective isotropically radiated power is the amount of power that a theoretical isotropic antenna (which evenly distributes power in all directions) would emit to produce the peak power density observed in the direction of maximum antenna gain. (from Wikipedia)
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