This thread comes at a good time for me, as I am planning an 8 circle array as we speak.
My installation will be an 84' diameter circle as I intend to us it on both 160 and 80m. My installation will be in the woods on a rocky hill (New England glacial moraine). I have found a plateau near the top of the hill where I can install the elements with all feed points at the same height. There is no area where I could put a larger spaced array at this location, and I am willing to trade-off some performance on 160 for coverage of 80m as well. I plan to go with the DXE kit, as i have been impressed with DXE products in the past. While reviewing the manual for the active receive antennas, I found that DXE recommends four to twelve radials at least 15 feet long, but no longer than 20 ft. I plan to deploy radials around each element due to the rocky area this array will be installed over, so I know radials will be required. My question is why the cutoff at 20'? Another question is would I benefit from a taller vertical element than the 8.5' whip included with the kit? 73 Greg N2GZ On Tue, Dec 16, 2014 at 9:35 AM, Joel Harrison <[email protected]> wrote: > > Greetings Bob & Reflector folks, > > Please allow me to provide a bit of my experience since I run both a broad > side/end fire passive 8 vertical array (350 ft diameter) with a DXE > controller AND a HiZ 8 vertical array spaced for 160 meters (220 ft > diameter). > > To your specific question about controllers both will perform very well > but there are differences in the arrays that need to be considered, so > please allow me a bit of bandwidth here to explain. > > I installed my BSEF array about five years ago when there was practically > no avalable information about the array and no commercially available > controllers. I built the array and a controller and published my work in a > paper on my website that later was published in QEX. > > Since that time, I have gained a great deal of experience with the array > both mechanically and eletrically and as a result of my published work > others have built arrays (w3LPL for one) had have shared their valuable > experience publically as well. As a result, I rebuilt my BSEF 8 vertical > array this year with a different mounting scheme like W3LPL uses and also > moved to a better controller that Mike, W9RE first made boards available > for and now that DX Engineering sells, which I now use for control of the > BSEF array. > > Over this time Lee's HiZ arrays have become quite popular and are > excellent performers. What I have noticed is there is considerable > confusion among the masses about the differences in these arrays and to be > quite blunt many folks equate living in an excellent geographical location > for 160 meters propagation to amazing performance of a specific RX array > which is an error. I am obsessed with 160 meter RX antennas and achieving > peak performance from my rural location in central Arkansas, an area that > is not enhanced by coastal propagation, etc. So I set out last year with a > personal mission to evaluate both 8 vertical array systems, the passive > BSEF array an the HiZ. I am not in the amateur radio business, I'm just a > ham with a desire to have the best 160 meter RX system possible for my > geographical area. > > So, both systems are operational here. There is significant sepeation > between the two arrays (>800 ft) and both are a significant distance from > the transmit antenna. Both have their own level of complexity with > installation and from personal experience I can tell you they each take > about the same amount of time to construct and install. > > I have already recorded several real on the air comparisons of patterns, > noise floors (taking in to account one is active and one is passive)and > several signal comparisons of DX stations (actual signal level about noise > floor, not S meter readings). I plan to publish these results in early > spring at the end of the 160 meter DX season for north america. > > I would be more than pleased to discuss any specific questions you may > have about these arrays off line a bit more in detail if you would like > but again the short answer to your question is both will be excellent > arrays. > > 73 Joel W5ZN > > > I'm new to 160 and am planning to add an 8-circle. I would like to buy > > commercial preamps and the controller. I would greatly appreciate any > > advice on the choice of preamp/controller vendor. > > > > I live in a rural area and have a 4-direction 3-ele vertical array for > > 160 with a 20+ dB f/b. So I'm looking for a beamwidth improvement on > > receive. Here are a couple questions: > > > > - Are the functions of the control network the same or similar between > > DXE and Hi-Z? (so I could use either one?) > > > > - DXE wants a 320' diameter and Hi-Z wants 200' for optimum performance. > > It's hard to tell what DXE performance is because it does not disclose > > RDF, beam width or F/B. And neither vendor supplies EZNEC files so I can > > see the effect of varying the layout. So I'm not sure how to decide what > > array size is best for me. It would be wonderful if someone has a model > > for these two systems. > > > > - If I use DXE, is it a no-brainer to use 24' verticals instead of the > > shorter supplied whips? > > > > - are there any best practices for weatherproofing the Hi-Z components? > > > > - are there any build-quality differences between the two that I should > > consider? I live in MT, so it is a harsh environment. > > > > Thanks! > > > > Bob, N7IP > > _________________ > > Topband Reflector Archives - http://www.contesting.com/_topband > > > > > www.w5zn.org > > _________________ > Topband Reflector Archives - http://www.contesting.com/_topband > _________________ Topband Reflector Archives - http://www.contesting.com/_topband
