DIRECTIVE SYSTEMS

PHOTO GALLERY

You may click on each thumbnail picture to see a larger, more detailed image.

KA1ZE Coudersport, Pa. Stan is putting together a heavy hitting single op station in FN01, at 2200 ft asl. in Western Pennsylvania. These photos show his 144, 222, and 432 antenna systems mounted on a large Rohn 55 tower, and how they got there! The rotating system is designed for easy one man maintenance. All of the antennas are readily accessible. Stan's plan is to assemble a top notch single op powerhouse in FN01. So far his results are very encouraging. The grid numbers are there. The problem is to get the QSO count up. Effective systems are needed to accomplish that goal. Stan is the Man for putting that system together. Now if he can just cut down on his commute of about eight hours from Connecticut to western PA!!

UPDATE Stan is solving the "commute" problem by automating and "remoting" his station. He made a number of January VHF SS QSOs while sitting on the beach in Florida. Way to go Stanley!

 

 

N3JPU Silver Spring, MD 2 X DS50-5 six meter yagis. He has a great looking website with all sorts of interesting links and such. He has used this array on 50 MHz EME with some good success. The antennas are stacked at 0.66 wavelengths to reduce local noise interference. Such close spacing in the vertical plane reduces any noise power coming from below the array. In some situations, this can be very beneficial. Similar gains can be obtained with close horizontal stacking. The penalty is reduced gain. With the digital modes, a slight gain reduction is more than offset by the increased copy gained from a quieter location.

WA8TTM Florida has a complete line of Directive Systems antennas from 50 MHz thru 10 GHz! Most of them are visible in these pictures. Ron has been quite a sparkpliug in building activity in Florida. It is a microwaver's dream where tropo can occur year round. All that water vapor can come in handy. Rumor has it that WA8TTM is moving back to Ohio soon. Darn!

K6QXY should get an achievement award from the Erector Set Company. Actually, it was the Gilbert Company, and erector sets were cool toys that allowed you to construct all sorts of creations with small metal structural pieces, bolts, and an electric motor. . Bob, K6QXY, has a back yard that looks like a giant erector set! He has made more 50 MHz EME arrays than I can count. One of his latest consists of eight DS50-5 yagis on a quasi polar mount, and constructed to hit the setting moon in Europe. How else are you going to work all those countries at the bottom of the sunspot cycle? "We don't need no stinkin' sunspots!" . These pictures provide much in the way of ideas for new projects. More here! A very cool antenna system!

ATTENTION! Most of these W1MRQ photos above, are high resolution and will load slowly on dial up connections. They sure look nice though!

W1MRQ Ernie, at McMurdo Base in Antarctica provided much in the way of excitement on 144 MHz in 2005, by operating EME from that exotic locale. A small system and WSJT JT65 software made all the fun possible. The plan was to have an array with a fat main lobe and some ground gain (Ice Gain) provide enough horsepower to make the Earth Moon Earth circuit. Four of the DS144-5LVA yagis were employed along with a 170 watt amplifier. The weather was so cold, he had to be careful so as not to snap the feedline into small pieces. Everything was very brittle. It was quite an undertaking and, according to Ernie, the most excitement he had experienced in years!.....................................For more on the KC4/W1MRQ story see here.

A nice wintertime picture of ice covered antennas at K2HZN, in New Hampshire, followed by another shot at WA1T, also in NH. I don't think too many QSOs were made when these pictures were taken! Ice looks pretty, but it raises havoc with yagis and loop yagis. Speaking of wintertime antenna shots........

The K1WHS station after a January 2006 snowfall. The left tower is 144 MHz. Then 50, 432, & microwaves. The 222 Tower is not visible off to the right. The middle photo is the 144 tower, a 130 ft Rohn 45. The last photo is a four yagi DSFO432-25 array in 1998 covered in 4 1/2" of ice. It survived the icestorm of the century very nicely.

 

N1GJ on Cape Cod has an array of Directive Systems yagis and loop yagis all compactly arranged on his tower for an effective multi band installation. The second photo is the 1296 array of KI7JA.

 

So the next time you hear W4RX in a VHF contest, he may be using this array. It is the largest LVA we are aware of, as of 2006, and is promising to get even bigger. Jim heard about (and heard on the air) the original K1WHS LVA and figured that he could use one at his place in Virginia in FM19. He went one better than the standard wide LVA and chose the six element DS144-6RS for more gain but with a narrower beamwidth. The sixteen antennas are stacked at 8 ft apart for a whopping 120 ft of vertical array height! The gain is about 6 or 7 dB better than his rotatable 4 x FO12-144 yagi array, which is shown in the third picture. Jim liked the first LVA so much, he is putting up another to point Northwest! We calculated the gain as somewhere near 22 dBd! In case you didn't notice, Jim is active on all the bands. I am sure that the FAA charts for near his QTH show a large magnetic anomaly. Quite an impressive collection of radiators!!

WA1ZMS Beacon Photos! In Late October, 2006, Brian, WA1ZMS, activated a new beacon on the East Coast aimed at central Europe. It utilizes our DPM144-5LVA yagis. It is being heard over a wide area!

WB3IGR uses this small 1296 Loop yagi, a 2314LYRM with a 36" boom. In the August 2007 UHF Contest, he worked 5 grids and 7 QSOs all with 5 watts. The conditions were not that great, and Geore was very surprised at how well the small antenna worked. The rear mount design makes installation easy for both vertical or horizontal polarization. A small 1296 looper can fit in almost anywhere on an existing tower.

Here is an interesting idea for hams who want linear polarization but need both horizontal and vertical modes. Check out the video file of ATV antennas by NR8TV. http://www.ki8hu.net/DavesAntennas.wmv Dave has a pair of 2345LY Loop yagis for 23 cm on a polarity rotation mount.

 

Moonbounce on 2300 MHz? With digital modes it is possible. Here is KA7V's effort with an array of four "custom" rear mount 33 element loop yagis and almost no loss in a feed harness. Each cable is 13" of 1/2" hardline! The antennas are mounted on an AZ- EL mount. Plans are to run about 400 watts of RF. The preamp is mounted at the power divider.