Home |
Search |
Today's Posts |
#10
![]() |
|||
|
|||
![]() Richard Harrison wrote: Cecil, W5DXP wrote: "If we simply amplify the receiver voltage through a near infinite impedance FET with virtually no load on the signal, do we get the signal information?" Not as much as possible. Just as the reactance must be tuned out of an antenna to receive maximum available power, to get maximum received carrier power, the resistance of the load in the antenna must be reduced to only that matcing the radiation resistance. Walter Maxwell, W2DU has had it right all along. Maximum power transfer requires a conjugate match. I happend across this just the other day. On page 1426, "Physics: Volume Two Electricity, Magnetism, and Light", Ronald Blum/Duane E. Roller it reads "Note that the optimum power transfer occurs when p=0, R=Z0, and t=1. [p and t are reflection and transmission coefficients] In general, for lossy lines, this takes place when the load impedance in the complex conjugate of the characteristic impedance, just as with lumped circuits." Seems to be the only way for p = (R-Z0)/(R+Z0) = 0 and t = 2R/R+Z0 = 1 to hold true for any Z0. ac6xg ac6xg Best regards, Richard Harrison, KB5WZI |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
Discone antenna plans | Antenna | |||
Yaesu FT-857D questions | Equipment | |||
LongWire Antenna | Shortwave | |||
Short STACKED Vertical {Tri-Band} BroomStick Antenna [Was: Wire ant question] | Shortwave | |||
EH Antenna Revisited | Antenna |