Home |
Search |
Today's Posts |
#11
|
|||
|
|||
Cecil Moore wrote in message ...
Mikey wrote: Yes, phased verticals will outperform a dipole. Some phased verticals will outperform a dipole, depending upon how one defines "outperform". It's more depending on the distance worked. A dipole at a decent height can have a 7 dB gain over a 1/4 WL monopole. His is at 30 ft. Yea, it might have 7 db max gain over the vertical. If he's working within 500 miles... A two-element phased vertical cannot equal that figure over average ground. Are you saying he should avoid radials, and use only the fairly lame "average ground"? No wonder none of your verticals work well... Cecil, I got news for you. A GOOD 2 el phased vertical setup would trounce a dipole at 30 ft at long distances past 1000 miles. A single GOOD vertical will beat the dipole on the same longer paths. Of course, I'm talking real verticals with the proper number of radials per height in wavelength, not some shortened loaded storebought junk, with no radials. Reference: Fig 10, Chapter 8, The ARRL Antenna Book, 15th edition. The maximum gain figure for a two-element phased vertical is 4.7 dB over a 1/4 WL monopole. The average is about 3 dB depending on spacing and phasing. That same graphic is Fig 11, Chapter 8, on the ARRL Antenna Book CD, ver 2.0. Gain fiqures are very misleading in this case. Tells only about half the story. You are causing more confusion than anything, because you don't properly apply the antennas to their proper jobs/paths. You never saw good results with yours because you misapplied it by using it for short paths, and also stunted it's performance by using too few radials. It never had a chance. EZNEC sez my simple 130 ft. dipole at 40 ft. has a gain of 10.8 dBi on 10m with a take-off-angle of 12 degrees. It would take quite a vertical array to equal that. (Then I would have to somehow overcome a +10 dB vertically polarized noise level. :-) What direction is all this gain? What will happen when you have to work someone in one of your nulls? Heck, I bet many of my old 5/8 ground planes would have equaled or beat your signal on 10m, to *most* people. I don't ever remember being beat by a simple dipole. In fact, when I used ground planes on 10m, I considered a horizontal dipole to generally be inferior. I know the ones I had were inferior to my ground planes at paths 1500-2000 miles away. And yes, some were long, and should have shown gain. They were over a wavelength high also. I wonder how your 10.8 dbi on 10m dipole would stack against my Cushcraft A4S beam? It has less gain according to the specs. But, I bet it beats your dipole on 10m in any direction if mounted at the same height. BTW, none of my 10m ground planes showed a 10 db increase in noise over my dipoles or other wire antennas. MK |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Inverted ground plane antenna: compared with normal GP and low dipole. | Antenna | |||
Want K2BT "Ham Radio" articles on phasing verticals | Antenna | |||
40 meter dipole or 88 feet doublet | Antenna | |||
QST Article: An Easy to Build, Dual-Band Collinear Antenna | Antenna |