Jim Brown-10 wrote > Beverages tend to favor higher wave angles, while verticals favor low > angles. Those who have lots of land like to install both Beverages and > vertical RX arrays (Hi-Z Antennas, DX Engineering are US companies that > sell them). I've seen reports of signals appearing an hour earlier on > one antenna than the other, then disappearing from the first antenna.
Beverages and vertical arrays actually have very similar takeoff angles (e.g. 25-40 degrees). Salt water dramatically lowers the lowest takeoff for verticals and a poor ground will raise it. Lengthening Beverages will also lower the takeoff angle. See Graph 3 below for an example of the latter on 160: http://www.seed-solutions.com/gregordy/Amateur%20Radio/Experimentation/Beverage.htm At 1 wavelength (~540' which is about the minimum useful Beverage length) the takeoff angle is 42 degrees. Lengthening it to 2 wavelengths lowers the angle to 27 degrees. Below are two plots (top and very bottom) of my antennas which demonstrate the difference between a low dipole (90 degree takeoff), a vertical array (22 degree takeoff) and a 2 wavelength Beverage (24 degree takeoff): http://users.vnet.net/btippett/new_page_10.htm I normally use Beverages on one port and an RX4SQ on the other port. I can also switch between the RX4SQ and my TX array (Spitfire variant). On 80 and 160 I use diversity almost 100% of the time. 73, Bill W4ZV -- View this message in context: http://elecraft.365791.n2.nabble.com/diversity-receive-what-bands-tp7580624p7580677.html Sent from the Elecraft mailing list archive at Nabble.com. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
