Home |
Search |
Today's Posts |
#7
![]() |
|||
|
|||
![]()
Reg Edwards wrote:
Reg, would you care to share your formula for velocity factor? ========================================== Cec, can't you find it in your bibles? Velocity = 1 / Sqrt( L * C) metres per second where L and C are henrys and farads per metre. What you really want to know is how to calculate L and C from coil dimensions. But you won't find that from any bible. . . . What seems to be getting lost in the discussion is that L is *series* L per meter and C is *shunt* C per meter -- that is, the C to another conductor(*). C is not the self-capacitance of the inductor. (*) Conductors also have capacitance to free space, but I'm not at all sure the transmission line equations for such things as velocity are valid if this is used for C. The equation for the resonant length of a wire in space is very complex and can't be solved in closed form, and even approximate formulas are much more complex than those for transmission lines. So while transmission lines and antennas -- or radiating inductors -- share some characteristics, you can't blindly apply the equations for one to the other and expect valid results. Roy Lewallen, W7EL |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
Self capacitance of solenoid coils | Antenna | |||
FCC: Broadband Power Line Systems | Policy | |||
Transmission Lines & Electrical Code | Antenna | |||
parallel transmission lines | Antenna |