Home |
Search |
Today's Posts |
|
#1
![]() |
|||
|
|||
![]()
On Thu, 2 Oct 2008 16:30:50 EDT, Michael Coslo wrote:
Hi Bill, Keep in mind that an antenna height that is NVIS on 80 meters, won't necessarily be so on 40 meters. I agree. My HF antenna is 3 dipoles, one each for 75, 40 and 20, suspended vertically with one foot spacing and fed with a common feed point. The top dipole is for 75, and the ends are about 25 feet high and the center droops to about 22 feet. Each dipole works independently (with mild interaction) because the desired dipole has a 50-ish impedance, and the other two have high impedances at the current operating frequency. I can operate on 75,40 and 20 with only my transceiver's built-in tuner (2.0 SWR max). I can also operate on 15 (third harmonic of 40) with an external tuner. On 75, I have NVIS. On 40, I can talk a half a continent away. On 20, I can talk world-wide. 73 de Dick, AC7EL |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
importing (modified) path profile data into Radio Mobile propagationprediction SW. | Antenna | |||
steve back on lie path | Policy | |||
UHF penetration & path loss Q: | Antenna | |||
LU1ZA QSL Path? | Dx | |||
LU1ZA QSL Path? | Dx |