Amateur Extra › E9 Antennas and Transmission Lines › E9A02
E9A02
What is the effective radiated power (ERP) of a repeater station with 150 watts transmitter power output, 2 dB feed line loss, 2.2 dB duplexer loss, and 7 dBd antenna gain?
Pick an answer to check it.
Answer: D. 286 watts
Net gain = 7 - 2 - 2.2 = +2.8 dB. ERP = 150 W x 10^(2.8/10) = 150 x 1.905 = about 286 W.
Tip: Add gains, subtract losses, then convert dB.