Home |
Search |
Today's Posts |
#2
![]() |
|||
|
|||
![]() "JIMMIE" wrote in message oups.com... While operating on 10M I have observed that a halfwave vertical dipole will communicate to different areas than a 1.25wl vertical monopole an example would be that during a band opening the 1/2 wl antenna may be working predominantly into New York while the 1.25 wl antenna is working best in California or was it vice versa. This has proven useful for me, instead of fighting a pile-up and can just talk somewhere else. The two verticals may soon be replaced with a tri- bander and I was wondering if I could get this same type of effect by tilting the antenna vertically(no change in polarity) with a remote controlled device. I think it would be pretty cool to hear different areas of the country pop in and out as the elevation of the antenna is changed. It would work, theoretically, for a small change but I doubt you'd ever notice the effect. You need a very directional (many elements) antenna to see a big difference in the amount of signal in the elevation plane. High gain UHF TV antennas do have tilters, but it's to match the angle of arrival of the signal, which may be coming out of a duct or reflected off a nearby ridge. See a sample at http://www.atechfabrication.com/prod...omy_tilter.htm Most tribanders are three elements and have a 3dB beamwidth of about 60 degreees in the azimuth (plan view) plane -- worse in the elevation plane. Further complication: The ground affects the shape of the elevation pattern, maybe more than any tilt you could apply. You might better fine-tune the angle of arrival by cranking a tower section up and down. "Sal" |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
Sound Effects Libraries For Sale! | Equipment | |||
Looking For Large Sound Effects Libraries? | Equipment | |||
Looking For Large Sound Effects Libraries? | Equipment | |||
Reducing effects of RF noise? | Shortwave | |||
Effects of solar storm on VHF | Shortwave |