Before revision: Wes Hayward, Doug De Maw (ed),Solid State Design for the Radio Amateur, Chapter 5 "Receiver Design Basics", American Radio Relay League 1977, no ISBN Gain is required because the signal intercepted by an antenna will have a very low power level, on the order of femtowatts ; to .
After revision: Wes Hayward, Doug De Maw (ed),Solid State Design for the Radio Amateur, Chapter 5 "Receiver Design Basics", American Radio Relay League 1977, no ISBN Gain is required because the signal intercepted by an antenna will have a very low power level, on the order of femtowatts .