"What? You're using whaaat as an antenna?!"

KØS, Kurt N. Sterba Strange Antenna Challenge

May 10-11, 2003

    Hello everyone! A great time was had by all during this Special Event. Our thanks to those stations we worked (QSL requests). We are sorry to have missed the rest of you, but maybe we will work you next year!

It really was great fun hearing the surprise in the voices of those that just happened across our signals, "What? You're using what as an antenna?!"

   Since this was our first "Strange Antenna Challenge" we didn't really know how well our "antennas" would work on the various bands. We felt 10-meters offered the best opportunities to actualy load our make-shift antennas.

    Obviously, a 10-meter wavelength is roughly 8 times smaller than its 80-meter counterpart. Therefore capturing a significant percentage of the band's wavelength should be easier on 10-meters. As such, only 10-meters was listed in QST.

    As it turned out we made the vast majority of contacts on 20-Meters, and were able to load aluminum extension ladders on 6- through 80-meters. We didn't try 160-meters. Next time we will provide a more accurate QST listing with regard to our planned bands of operation. We will, however, still try to remember to stay in the General Class areas of each band.

    Below you will find images of each antenna we used along with a listing of those stations we worked. An explanation of each set up is provided and you are invited to email questions you might have, or to request additional information. Since the site closed early I did not obtain images of the feedpoints, baluns, and other fine details of the operation. However, suitable alternate images are posted.

    Thanks for seeding this great idea Kurt, it was a blast!

View Misc. Images (Specific Strange Antenna Images Are Below, By Antenna)

Saturday
Evangel Library, Springfield, MO

May 10, 2003
10 AM - 1:30 PM (central)

    Saturday there were high winds (gusting well over 30 mph), thunderstorms, and tornado watches throughout the day. At 1:30 PM (local) our Skywarn group was activated. Since many of our operators are active Skywarn members this is when we shut down the site at Evangel Library.

    Still fresh in everyone's mind were the recent tornados that swept Missouri the previous week. Huge amounts of property damage took place and nearly 20 peopole were killed in Missouri alone. Needless to say, we were taking the threat of severe weather very seriously.

    Our local paper published a well written article appearing below the fold of the "Ozarks" section.

    For those of you counting, we were left with approximately 3 1/2 operating hours at the special event site. Not a very long time compared to our planned operation. This greatly diminished the number of contacts we were able to make during this special event, as well as the number of strange antennas flown. We would have liked to have experimented with many more configurations, and to have flown the shopping carts and dog kennel.

    After the library site closed each person was "on their own" and operating from their homes, or other sites selected by themselves. Since it was Mother's Day, and the thunder storms caused a lot of minor damage and power outages, it seems that only Dwayne, wb5plj, and myself actually operated Sunday. Everyone else chose to spend time with their families or were called to work. Priorities people!

    Unfortunately 10-meters was dead. My apologies to those of you seeking us out on 10-meters for naught. I would like to thank my fellow 10-10 members for kindly posting the event information in their newsletter and on various web sites. The rest of the bands were in-and-out all weekend. Quite a bit of QRB was present both Saturday and Sunday. (Suitably strange come to think of it.)

A-Frame
Double Extension Ladder Verticle

    More images...

    This employed two metal extension ladders (which were later used to make the dipole). One is a standard 14 foot ladder and the other is a "mutli" ladder which was shaped into an "A-Frame" shape and driven as the radiating element against the other (the ground plane). Scrap 2x4s were used to insulate one from the other.

    The feedpoint was on the ground where the two ladders came in close proximity to one another. The coax was simply stripped back, exposing the two wires inside (center and shielding) which were pressure fit against the ladders. Center conductor to the "A" and the shielding to the ladder resting on the ground. No coax choke was used so there are no meaningful SWR measurements (due to energy flowing along the outside of the shielding back to the station/meter), but it loaded up fine and good signal reports were given by both stations.

    This was the first antenna to make contacts. Our very first victom was Bill, k7zm, in Bend OR who was "also" using a verticle antenna. Very clear communications were established and the QSO was easily made. The reporter seemed somewhat surprized we were talking to OR. Methinks he doubted our apparently crazy plans would come to fruition!

    In all seriousness, both the reporter and the photographer genuinely seemed interested in what we were trying to accomplish. Both listened to our explanations and digested the information without signs of indigestion. I think they got it, now if they'd get their tickets...!

Top Hat
24-Foot Verticle Extension Ladder
With Stand-Off As Top Hat

    This is the "Top Hat" verticle we made from Dick's (k0gl) ladder and Erik's (n0ew) chicken wire screen. The ladder is driven as the radiating element and the chicken wire as the ground plane. Scrap rigid insulation serves to isolate the two elements from one another.

    In the foreground near the base, you can see the moving dolly. Both were sitting on the same chicken wire ground plane. The chicken wire was a roll measuring 3x25 feet.

    We made several contacts with this verticle ladder and I'm certain we would have made many more had we been able to operate all day as planned. It tuned up quite well using a MFJ-969 tuner.

    I don't recall the all various bands we tuned this up on, but I know it tuned up very well on 20, 40, and 80-meters. This ladder has the widely spaced support arms near the top which is why we referred to it as the "Top Hat" verticle.

    A 24-foot ladder is a tad large to carry in your "go bag" but if you were to lose your antennas and happen to have one or more of these around the house, you would be able to get out a decent HF signal.

    The call with the "?" following the call means I am uncertain of the log. The hand writing was unclear to me. Should I be able to confirm / deny this entry I will upgrade the log.

Dipole
Double Extension Ladder Dipole

    More images...

    We took down the A-Frame Verticle to make this Dipole. It was made from two aluminum extension ladders, end to end. We used fiberglass step ladders to hold up the aluminum ladders about waist height.

    These could have been placed a little higher on the step ladders, about doubling the height above ground, although still quite a small fraction of the wavelength. Since the taller step ladder was in the middle the feedpoint could have been a couple feet higher than the far ends. Every little bit helps! With a dipole, getting the feedpoint away from the earth is generally a wise plan.

    Another idea was to suspend the two ends from the trees. We had a tree on either side and this would have gotten the free ends up at least 10 feet and the feedpoint, again by using the taller step ladder, could have also been roughly as high.

    There were most likely other ideas we could have tried, had it not been for the storm rolling in. But this is what next year is for!

Shopping Cart
Dipole

    More images...

    We tuned these up on 10-meters but were unable to hear anyone or make any contacts.

    They were sitting on the ground about 20 feet from the pavillion. We did not find time to return to them, or to attempt elevating them in some fashion.

    We borrowed these from Smillies IGA, and yes, it was fun explaining why I wanted to borrow their shopping carts for the afternoon! They seemed to get a kick out of it. In any event, it was a little disappointing to not fly these since they are as close to "traditional" as one can come (well, a patio umbrella is pretty traditional too)!

Moving Dolly
Verticle

    This was sitting on top of a 3x25 foot strip of chicken wire ground plane, and insulated by a pieces of 2x4 scrap lumber. There was a bucket of string sitting on the blade of the dolly to keep it stationary.

    I was able to tune this up on 10-meters but as with the shopping carts, I was unable to hear anyone or make any contacts. This was unfortunate as our only published frequency was 28.500 MHz.

    We did not try tuning this up on any other frequency. For a comparison you can go to the ARRL 10-Meter Contest. During that contest I had this dolly sitting on my roof at home (roughly 12-14 feet above earth) and was able to make a number of contacts.

Sunday
Residence of nØew, Springfield, MO

May 11, 2003
10 AM - 12:45 PM, and
 3 PM - 7 PM (central)

Loadlock Verticle
Small Fence Ground Plane
   Resonate Frequency = 16.0 MHz @ 1.01 SWR

    More images...

    Close ups of feedpoint, coax choke, etc....

    A "Load Lock" is a tool used by truck drivers to help keep their loads from shifting in their trailers as they drive across our country. This one is metal, approximately 8 1/4 feet long, and in two sections that are pinned together. (This allows it to collapse to roughly 4 feet for storage.)

    For a ground plane I used a small chain link fence that has two 20 foot runs set at 90-degrees to one another. The loadlock was orientated roughly in the middle of one side, and supported by a fiberglass step ladder.

    The images I took Sunday did not turn out. The images of this antenna are a mock-up of the one used. Essentially the only difference is the loadlock was actually on the other side of the step ladder and there was a single guy rope running across the sidewalk to keep it from blowing over.

    My friend Dwayne, wb5plj, and I worked this loadlock in three different configurations Sunday. In the verticle orientation shown here, in an "L", and as a sloper.

    There were a number of interesting contacts in this run. Steve's K2 sounded great, and with only 10w still was perfect copy. Pretty good for a dipole up 25 feet. This is just the latest in good tales I am hearing about these rigs. My friend wb5plj has one still in the box. I am looking forward to hearing it on the air and his tales of woe and excitement as that project progresses. Ifins it goes well, I may follow suit!

    I was happy to provide the second report for k2bh operating near the USMC base near Perris Island. This is how we learn. For anyone remembering this for next year, feel free to check in with me more than once if you are making changes to your station or antenna system.

    I greatly enjoyed the conversation with Leon, w4yfz. He is a retired antenna engineer, an active member of the motor home mobile group, and the only person to provide his wattage in RMS (I am the one that called that 700w peak, not Leon, so flame me for the inaccurate estimate). They hold a net on 14.263 at 1 pm central. You should spin your dial by there if you are in the mood for a pleasent conversation. 73 Leon!

Loadlock "L"
Basketball Hoop Ground Plane
   Resonate Frequency = 26.9 MHz @ 1.2 SWR
   Rs = 42; Xs = 8

    More images...

    This time I suspended the loadlock from a nearby tree so it was about 10-feet above the earth and roughly horizontal and pointing to the south (and ever so slightly west, but not so far as south-southwest).

    The ground plane was a basketball hoop and support pole. The pole was metal and about 10-feet tall with the basketball board & hoop attached by metal supports.

    Of the strange antennas used at my house Sunday this one was the least effective. It tuned up fine, but I don't think it was effectively radiating.

What's that? A field strength meter, as recommended by Kurt N. Sterba? What a great idea! It just goes to show, as Maxwell said you can have "low SWR for the wrong reason".

    For whatever the reason, it doesn't seem the basketball hoop's pole provided a very good ground plane. It may have been its paint was thicker and therefore the electrical connection was insufficient, or there just may not have been enough metal to allow the return energy flow to be effective.

    I do find it interesting the resonant frequency was so much higher than when the same loadlock was flown above either fence. Nearly 27 MHz from the basketball pole, versus 16 MHz when either the large or small chain link fences were used. Certainly either fence was long enough to establish two return paths serving as radials for the verticle element.

    This may be demonstrating the difference between running a verticle element with essentially a large ground stake (the pole) versus actually providing a direct path for the ground plane energy to return to the antenna system (via the fence). Radials provide "lift" to the RF signal.

    Note the height of their antenna... 200 feet above the earth. It is mounted on top of the Science Center in downtown Phoenix. They were the only station I heard over the course of calling CQ for about one hour. I figure this is a case where they only heard me because their antenna was exceptional.

Loadlock "Sloper"
Large Fence Ground Plane
   Resonate Frequency = 16.3 MHz @ 1.1 SWR
   Rs = 55; Xs = 3

    More images...

    Once again using the loadlock as the radiating element. I used two fiberglass step ladders (one 6 foot and one 8 foot) to support the loadlock at roughly a 30-degree angle and pointing east.

    A large neighborhood chain link fence served as the ground plane. I have not walked the entire length of this fence, but it runs down the entire block and sections off a number of homes, so it is in fact a "large" ground plane.