Antennas And Tuners
















Portable End Fed Zepp
Also Known As The No Counterpoise Antenna
I Call It The FIVE MINUTE – FIVE DOLLAR ANTENNA


I first saw what I now call the 5 minute - $5 antenna mentioned on a QRP reflector by Peter Millis , M3KXZ. Pete called it the “No Counterpoise” antenna, and he’s done considerable EZ-NEC work on it. Additionally he’s phased two 20M versions in a vertical configuration.

The No Counterpoise is a neat version of our old friend, the End Fed Zepp..

I’ve used EFZ’s over the years, along with many other cheap and easy wire antennas. Some I’ve actually called Cheap and EZ’s - doublets, really long doublets, dipoles, verticals, long wires, not so long wires, short wires, tall verticals, short verticals, etc. etc.

I have returned often to the EFZ because it seemed like the ultimate multiband Cheap and Easy antenna to me. It’s easy to build, easy to erect, easy to tune and easy on the pocketbook. It does require a tuner most of the time, but if it’s used for a single band, the radiator and the feedline lengths can be adjusted so a tuner may not be needed.

As is common knowledge, a true End Fed Zepp is a half wave radiator and a quarter wave balanced feedline. It has many followers and proponents, at least I hear and see it mentioned often. Maybe not as often as the gold standard dipole or center fed doublet of some length, but often enough. Why do some of us like them? Because they’re quick, cheap, easy, and they work. One attribute that is often seen as a negative is actually a positive in this antenna, the feedline radiates. Since it’s up in the air that’s not a bad thing, especially at QRP levels. Easy to Build … Easy to Erect … Easy to Tune… and Cheap too A few real life examples will help illustrate these points.

Example #1 … Home QTH A small, semi-hidden factoid is that it doesn’t have to be the classic EFZ to work quite well. Since I moved into town I’ve been cramped for space, my city lot is rather small, even for town. Luckily I have a very nice neighbor who loaned an antenna support to me, of course he thinks it’s a tree. From the 60 foot top of his tree down the 20 foot tree in to my back yard is just right for a 111 foot wahr, err wire. I could have used it as a long wire, but decided to feed it 450 ohm ladder line. An electric fence insulator was installed on each end, one side of the ladder line soldered to it and the other end was run into the basement. I shot a couple of arrows into the air (carefully) and hoisted the ends up and that was that, done - quick an easy. Easy to build and easy to erect, but was it easy to match? Yes indeedy! I installed an SGC 239 autotuner on the inside basement wall and it matched the wire perfectly from 160M to 6M, and everywhere in between! It’s no red hot DX antenna, but it gets out reasonably well on all bands, and I have worked a fair amount of DX on it, in the last 2 years.

Example #2 … Portable Ops. I’ve been using a 50 foot version of the no counter poise/end fed zepp/ end fed random wire/whatever for several years now for portable ops. It’s a 25 foot radiator fed with a 25 foot balanced feedline. My BLT matches it well on 40 and up, and it’s easy to put up. Just throw the far end into a tree and the feedline end guzzinta the camper or taped to the picnic table. It’s seldom been more than 30 feet up, and still works fine. One additional attribute is that it seems to be less succeptible to hand capacitance than a wire and counterpoise. I’ve put up a 100 footer to cover 80M and up, and it worked well also. So well that I decided to hack my venerable BLT to cover 80M. I wound up using a T-Match to get it, but that’s another story..

Example #3 … WØMQY’s QTH Last August Joe invited me stay with him while attending the Joplin hamfest. Of course we hooked up a rig and made a few contacts.. We made up and threw up a 50 footer in his front yard, ran the feedline in the garage and fired up a rig on his van’s tailgate. We worked a few and entertained some passerby’s at the same time. He was using a manual tuner, I think it was a Z-100. The antenna didn’t load well on 40M and later we decided that it must have been due to the feedline’s close proximity to the garage’s aluminum siding. The After the hamfest on Saturday, Gene, NØMQ , came by for a cookout - we ate first and played radio second, or maybe that was the other way around.. The food was first rate, and so was the radio’n. Gene brought his No Counterpoise, purchased on Ebay, and we gave it a workout. As expected it worked well with the far end up about 30 feet and the near end taped to the deck railing. Many stations were worked that evening before the mosquitoes finally drove us inside. The following day Joe hooked his antenna up in the same tree that Gene used the night before and it played properly, matching nicely on 40 and up. Proving that the aluminum siding was the culprit the day before.

So what’s the 5 minute - $5 thing all about?

As mentioned above, Pete, M3KXZ, called it the “No Counterpoise” antenna. I call my 40M version the 5 minute-5 dollar antenna because I make it from a $5 -50 foot roll of Radio Shack speaker wire, and it takes only about 5 minutes to make. Here’s the quick steps, 5 minutes total time - guaranteed…

1. Unroll it
2. Split it back halfway
3. Cut off one side
4. Tie a loop on the end of the single wire
5. Strip and tin the ends of the feedline

That’s it! Antenna building doesn’t get any easier than that. Give this Cheap and EZ antenna a try. It’s great for portable ops and it proves my antenna motto: “Try It – It Might Work!”


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322 foot Doublet
This Antenna Is No Longer In Use Due To Moving Into Town
It Worked Like Gangbusters, and I really miss It.
The main antenna here is a BIG doublet. It's 322 foot long fed with 450 ohm ladder line, and its about 30 feet up. The ladder line comes down the side of the house and into the basement where it is connected to an SGC-239 . Then it's a 15' coax run up through the floor into the shack. It tunes well on all bands 160M thru 10M.

However, while running QRP, the tuner would come unlatched and hunt, find a match and relatch, stay for a few minutes, unlatch, etc, etc. That was disconcerting since most QRP rigs dont have sophisticated power fold back circuitry to protect the final. Usually they employ a zener diode from the final's colletor to ground.

I surmised that rf getting into the tuner was causing problems. First I tried a better ground, closer to the tuner. That helped some but didn't eliminate the problem. The next step was to install a choke balun between the tuner and the feedline. That made the tuner was made much happier. Now it tunes near 1:2:1, and stays latched up....

The balun I used is the W5YR bead type choke balun This balun is cheap and easy to make, It is five 1-1/8 ferrite beads, type 43 material, Fair-Rite #2643540002. These are the right ID to slip over RG-8X coax. George Baker, W5YR (SK) developed and suggested this balun design in QRP circles. It may not handle QRO power for very long, but I think (no real data here) that its good for 50 - 60 watts, CW duty cycle.. At least it didn't get warm when I put 80 watts through it for 1 minute with 40 meter energy, and the tuner stayed latched up the whole time..


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OzarkCon Dummy Load Special Antenna
Last year at OzarkCon 2007 a Dummy Load QSO Party was held,
and a tradition was begun.
Prior to OzarkCon 2007, several noted QRPrs had expressed an interest in operating during the event. Setting the ball in motion, WØIIT, Bart, obtained the special event call, KØN for use during the conference. It was decided to hold a Dummy Load QSO Party for the attendees wherin they could contact KØN from their motel rooms during the conference. It was very successful and many contacts were made with KØN as well as as room to room QSO's. Special KØN QSL cards were distriubuted for those contacts. KØN contacts were made across the country as well, since the special event station had an outside antenna. The Dummy Load QSO Party is thought to be the first one of it's kind.

However, Some of the Dummy Load contacts were nearly ESP due to the semi shielded nature of the dummy loads in use. The antenna described here provides much stronger signal strength while staying within the concept of a dummy load antenna.

This "pseudo" antenna has proved itself from a room at the 2008 St. Joseph, MO hamfest site. Joe, WØMQY, heard it plainly 3 blocks away from the motel. At -10 deg F he was too cold to attempt a QSO,but declared the signal plenty loud enough for one, It was S9+ in the motel's parking lot. So with that performance I herby name it the OzarkCon DL Special and invite all to duplicate it for the upcoming 2008 OzarkCon Dummy Load QSO Party. Just tape it on the wall in a big rectangle and have at it.

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SVCC




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