From k7tjr at msn.com Mon Oct 11 12:34:09 2010 From: k7tjr at msn.com (Lee K7TJR) Date: Mon, 11 Oct 2010 09:34:09 -0700 Subject: [Hi-zreceivingarraydiscussions] 8 element array Message-ID: Dick and I installed an 8-200 160 meter array right out of production among the carrot plants last Friday. I have to take it back down tomorrow because they will be harvesting. What a treat, I listened to many Europeans during the evening for three days, and many Pacific in the early morning. I am trying not to brag because I am very critical of my own work, but this array is just KILLER. I am listening to IV3PRK as I write this. He is perfect Q5 copy on the array and just a few peeps on the TX vertical. If I switch one click either direction he is nearly gone. Just like the recording demo on the www.hizantennas.com web page. We are building stuff as fast as we can to fill all the orders. All I can say is hang in there, the wait will be worth it!! We are catching up!! The latest customer to report is Joe K2XX, whom just finished building his 4-square and reports: " In every case signals received on the array were much easier copy. Usually, when I switched to the vertical the signals were audible but difficult to copy or uncopyable. " Thanks every body for the continued support. Lee K7TJR From g3rcq at yahoo.co.uk Tue Oct 12 15:19:35 2010 From: g3rcq at yahoo.co.uk (David Cole) Date: Tue, 12 Oct 2010 20:19:35 +0100 (BST) Subject: [Hi-zreceivingarraydiscussions] (no subject) Message-ID: <782978.67389.qm@web29720.mail.ird.yahoo.com> Hi all - I have just read Lee's posting - Lee I am hanging in!!! I have placed in position 8 verticals 23feet tall - ready for the 80m 100ft circle array, this weekend my Son and I are burying the 8 x 50foot cables together with 800feet of feeder - the array is located in the middle of cornfields. I will be posting results asap - keep building Lee (faster!!) - I have a full size 80m 4 square array and reversable beverages on which to do the comparisons. Regards to all - call me on 80m dx end most sunset/sunrise times. Dave G3RCQ From bzavrel at meteorcomm.com Wed Oct 13 13:08:49 2010 From: bzavrel at meteorcomm.com (Bob Zavrel) Date: Wed, 13 Oct 2010 10:08:49 -0700 Subject: [Hi-zreceivingarraydiscussions] Homebrew 4-square based on Hi-Z amps Message-ID: <2CE535335AEB4E4EBABD79DC523A0B86015479611F8D@MCCMAIL01.MeteorComm.lan> I just finished building a homebrew 4-square. The elements are 21 foot sections of 1 ? galvanized pipe. I mounted 12 foot pressure treated 4x4s in the ground with cement. A metal pipe stand-off is used about 9 feet off the ground...the end is threaded, so a PVC threaded "T" is screwed on the metal pipe stand-off...then the 21 foot element is inserted through the T. The threading connection acts like a hinge. The bases use plastic funnels (like for oil drainage) upside down on small boards...that's all there is to the mounts. Plastic drain pipe keeps the amps dry, and extra coax lengths are wound around maritime-type rope fasteners...to keep the coax from running rampant, and looking ship-shape. The homebrew controller can select 8 directions on both 80 and 160 meters. I can check the integrity of the four feedlines and the pre-maps from the shack by simply monitoring the current consumption to each element. I use 1 ohm resistors in series with the supply lines to each amp and then shunt with a 100 ohm resistor in series with an old 0-1 mA meter... a rotary switch selects the element to be measured. The current consumption is remarkably consistent among the four amps (about 30 mA each). I use identical feedlines to each elements (240 feet each), and use passive L/C phase shifters rather than transmission line phasors. This allows me to fine adjust the phasing in the comfort of the shack. Without adjustment, I achieved >25 dB F/B ratio..fine tuning for slight environmental variations (temp, moisture, etc) can null better than 30 dB F/B. Amplitude balance of the amps/lines is excellent. The amps are everything I hoped for...the weakest links in the array's performance are environmental and phasing accuracy..not the amps. I also use the Hi-Z 75/50 ohm transformer to convert the entire system's 75 ohm standard to 50 ohms just before the RX input. I use the Curtain-Zepp (last April QST) for TX. Since the directive pattern is tighter on the 4-square, the S/N ratio is about 3-4 dB better on the 4-square. I use a simple 1.843 MHz clock oscillator run on 3 AA batteries mounted in an electrical box. A 10 foot wire acts as an antenna. I place it about 200 feet from the array and can measure F/B ratios very accurately by turning off the RX AGC, and measure the difference in audio voltages...the dB differences will give you a very accurate mapping of the pattern. The unit is still generating a very low-power signal 2 weeks after turning it on...just enough to give me a reading. The controller is a very flexible operating unit, but also was designed as an experimental platform. See you on the bands! Bob, W7SX From w8car at buckeye-express.com Fri Oct 22 16:06:58 2010 From: w8car at buckeye-express.com (Dan Kovatch) Date: Fri, 22 Oct 2010 16:06:58 -0400 Subject: [Hi-zreceivingarraydiscussions] 3L array info Message-ID: Greetings to the list. I have just installed the 3 L 50 foot spaced array from Lee and am posting some general comments. I currently have several RCV ants including a NE EWE, SE Flag, a NW pennant and a West heading BOG of about 300 feet. In the winter I can usually get out a BOG to my NE that is around 300 feet long. I ordered the 3L antenna because I really can't seem to squeeze a 4 L into my acre without surrounding my 160 and 80 meter transmit antennas. I am looking for better coverage to my NW as the pennant seems to not hear very well in that direction and I also needed some better coverage to Africa. So, the 6 directions seemed a good compromise. I have mine setup so the array (in position 1)points at 45 degrees from my qth as that is the best heading for EU. The array was purchased complete except for the verticals and interconnecting cables. I made the elements from from an old 10 meter beam mounted on 4x4 posts of about 7 feet with 3 buried. PVC is used for insulators with a 4 foot ground rod at each element for the preamps as per directions. I had some relay control lines from other antennas left over so supplying power and control switching was no problem. So far condx have not been very good for DX on 160 and 80 but I've been listening on the AM BC band with great results. At times I can replace a station in one direction with another by changing directions. Also, there are many times when a BC station that is S9 will go into the noise on one or more positions of the array. The limited EU and S DX I've heard has been equal to or slightly better than the the signals on the other listening antennas. The comparisons at this point are very subjective because each antenna has a different amount of signal and noise level. What is apparent is the angle of arrival of DX signals has a great impact on signal strength. The array will give me another 'bolt in the quiver' for DXing on 160 and 80. I'm very pleased so far with the quality of the product and ease of setup. Now that all the cables are buried I can sit back with a cup of cocoa and look for that DX!!! Dan W8CAR