Chuck, I don't have the experience with both that Dennis has but I have had the same beneficial results with the HI-Z 4-8Pro Rx antenna which I'm using 8 active short antennas. Sometimes I can null another station almost totally out of the picture. There's not that much gain compared to the sloper but the S/N is far better on the HI-Z. I consider it essential.
I understand you're talking about Tx as well but I wanted to share my similar Rx results as Dennis has had. 73, Gary KA1J > Chuck > > Having used both at a number of stations, I can speak with some > experience here. > > The biggest virtue I have found of an 8 Circle array is the ability to > put a bothersome station or noise in a null. Most of the time, you > can hear a station in the 4-square beamed direction as well on the > 4-square as on the 8 Circle. You might even be able to put a > bothersome station or noise in a null with the 4-square, but now he > doesn't hear you either. The 8 Circle allows you to steer the null and > maybe find a spot where the SNR is better, and I've found both as > valuable as the direction of maximum gain. > > So, yes, you can hear things on an 8 Circle that you might not hear on > a 4-square, but to me its more a question of nulls (of both other > signals and noise) rather than a stronger signal. > > Dennis W1UE > > On 10/16/2017 2:26 PM, Chuck Dietz wrote: > > I was always told that, if one had a 4 square, there would be no > > need for a receive array. I am finding this to be untrue when > > looking at the list of RDFs. (Receive Directivity Factor) I have > > snooped through the archives reading about RDF. Can anyone verify > > this from actual experience? Can you actually hear stuff on an 8 > > Circle that can't be heard on the transmit 4 square? I would think > > the difference might be more than marginal with the difference in > > RDFs of 2.48 db. I'm not sure of the difference in takeoff angles. > > That could be important too. As a practical matter, the 8 Circle is > > huge and expensive for a single band antenna... > > > > Chuck W5PR _________________ Topband Reflector Archives - http://www.contesting.com/_topband