FCC Element 3 Practice Test 2026 – Complete Exam Prep

The effective radiated power (ERP) of a repeater depends not only on the transmitter's power output but also on the losses incurred through the system, as well as any gains from the antenna. Generally, the effective radiated power can be calculated using the formula:

\[ \text{ERP} = \text{Transmitter Power Output} + \text{Antenna Gain} - \text{Line Losses} \]

In this case, if we consider a transmitter power output of 100 watts alongside the specific losses in the system, the calculations would reflect those losses, resulting in a figure greater than 100 watts but less than double the transmitter power output.

If the specific losses (and possibly antenna gain) bring the effective power up to about 126 watts—factoring in those technical details—this leads to the conclusion that the correct answer reflects the accurate calculation of the effective radiated power, which totals to 126 watts in this instance.

This indicates an application of the formula and a clear understanding of how transmitter power interacts with external factors such as antenna gain and line losses to determine the effective radiated power for the repeater.