Home |
Search |
Today's Posts |
#11
![]() |
|||
|
|||
![]()
I think Reg's estimate of both inductance and first self-resonance (or
is that self-anti-resonance?? ;-) are a bit high. Methods I trust all predict about 97uH and self-resonance at very close to 8MHz, for a coil wound with 16AWG to a 2-inch inner diameter. (Inductance would be a bit lower if that's the wire center-to-center diameter.) Winding and measuring one to see which estimate is closer is left as an exercise for the reader, but I wouldn't trust either Reg's or my estimates on this for building an inductance standard (and besides, I'd build such a standard with a lower L/D). A transmission line model shows 13.5 electrical degrees of line at 1.9MHz, at about 6140 ohms. You should probably look up an article by John Mezak that appeared in "RF Design" some years ago before you to applying that info willy-nilly, but I don't really expect you will. Have fun. Cecil Moore wrote: Reg Edwards wrote: A 100 turn coil, 10 inches long, 2 inches in diameter, has an inductance of 102 microhenrys, a Q of aproximately 380 at F = 1.9 MHz, and the self-resonant frequency is 12.0 MHz. Its radiation resistance at 1.9 MHz is negligible. Good stuff Reg. Modeling it as a transmission line, what would be its Z0 and VF? -- 73, Cecil http://www.qsl.net/w5dxp |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
Current in Loading Coils | Antenna | |||
FCC: Broadband Power Line Systems | Policy | |||
FS: sma-to-bnc custom fit rubber covered antenna adapter | Scanner | |||
Current in antenna loading coils controversy (*sigh*) | Antenna | |||
Current in antenna loading coils controversy | Antenna |