A transmitter has a power output of 125 watts. There is a loss of 0.8 dB in the transmission line, 0.2 dB in the antenna tuner, and a gain of 10 dBd in the antenna. The Effective Radiated Power (ERP) is:

To find the Effective Radiated Power (ERP), start by calculating the net system gain in decibels. The antenna provides a gain of +10 dBd, but you must subtract the 0.8 dB transmission line loss and the 0.2 dB tuner loss. This results in a net system gain of +9 dB. We can calculate the power multiplier by breaking the 9 dB into 3 dB increments. Since every 3 dB increase doubles the power, a 9 dB increase means doubling the power three consecutive times (2 x 2 x 2 = 8). Therefore, the overall power multiplier is 8. Finally, multiply the original transmitter output of 125 watts by 8 to get the ERP. Calculating 125 watts times 8 equals exactly 1000 watts.