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The Hentenna Yagi September, 2012 So I was studying antenna theory and looking for information about building a 2-meter Yagi so I could easily use my HT from the house when I stumbled across an article and plans for a 4 element "Hentenna" beam antenna. That article at http://www.hamuniverse.com/n5nns4elhentenna.html inspired me to try one for myself. It seemed simple and straight forward - probably because I didn't put too much thought into why or how it works. I had most of the construction material in my garage - one of the big reasons I chose this design. PVC, AWG 16 wire and plenty of it, and the lumber. The only things I lacked were coax and PL-259/SO-239 connectors. I started construction on September 18th, building the driven element first which was also usable as a stand-alone antenna (the original "Hentenna" is a single element). It didn't take me long to have it all together and I got to learn how to solder in the first half hour. This was my first real building project of any kind - ever - that didn't involve restoring an old car/truck. September 19th took me to Radio Shack for some RG58 and the PL-259. I had already determined not to use an SO-239 since it would be easy enough to solder the coax directly to the feedlines - making the build just that much cheaper. Sounds so easy, doesn't it? I got the driven element together and soldered the coax to the leads just as planned. All Radio Shack had available during my trip was the crimp-on style PL-259's. I knew it was very low quality when I bought it, but I went for it anyway - rookie! My testing of the driven element began at 1:30pm local time using my Yaesu FT-50R at 5 watts and a borrowed SWR meter. First reading was 2.2 SWR. I wasn't that surprised considering the Hentenna requires a significant amount of adjusting to the feedlines for a 1:1 match. N5NNS's article told me that much. I adjusted the leads up and down for a good 20 minutes before I finally gave up, realizing I had a bigger problem. I could have thrown the antenna in a pool and it would have still given a 2.2 SWR reading. There was no signal getting to the antenna. Over the next few days I conferred with many of the local hams on our morning "commuter's net", as I call it, and a few others as well. Everyone was stumped. As they asked me questions and I have specific answers which eliminated their theories, no one could come up with an idea - except bad coax. I even tried several new cuts of coax, but I only had one box of unterminated coax to play with so if the whole box was bad it wouldn't really make a difference, right? But what were the chances of a whole box being flawed? I certainly wouldn't put any money on it. I even built a quick and easy 2-meter dipole just to make certain it wasn't the antenna. That 2.2 SWR was haunting me. I finally took the whole rig out to a friend of mine, Mark (AD5WI), who did some additional testing on the connections. Sure enough, the crappy PL-259 I got from Radio Shack was the culprit. I had now been fighting with this antenna for a full week and was thoroughly frustrated so I still wasn't going to get my hopes up until I saw it finally work. On September 24th, a day after my 30th birthday and two days after I passed my General Exam (Hey! /AG!), I stopped at Radio Shack again (don't judge me - I didn't want to wait for mail-order!) and bought some pre-terminated coax and an SO-239. After fixing the antenna up with the new SO-239 connector, I took the driven element out to test again. I had the HT on the weather band when last I'd used it so when I plugged everything up and turned on the radio I was thrilled to start immediately receiving! That meant the radio was actually getting signal from the antenna! Step in the right direction, but certainly not a success yet. Now for the testing phase. On September 24th, 2012, at 1:50 pm local time, I tested the driven element on 144.00 MHz and found a 1.6:1 SWR. I then tried 146.00 MHz for a perfect 1:1 match and then 148.00MHz for a 1.2:1 SWR reading. It worked! My "Hentenna" was actually working! It was quite a relief after all that I'd put into this thing so far. My very first antenna worked and, better yet, it was a perfect 1:1 match at the center of the band without a single adjustment! But, I still wasn't sure how placing it inline with the other elements would change the dynamic. I began work to build the rest of the antenna and a few hours later I had a full 4 Element Hentenna Beam ready for testing. It took me a little longer to find a large PVC pipe that would support this massive 2-meter beam that weighed in at almost 30 lbs, but once it was ready I took it up to my 2nd floor deck and strapped it to the railing for the test phase. On September 24th, 2012, at 7:12 pm local time, I tested the full 4 Element Hentenna Beam on 144.000MHz and found a 1.2:1 SWR. At 146.000MHz I got another 1:1 SWR reading and on 148.000MHz it was 1.5:1 SWR. The antenna worked. First time out, it worked! My very first antenna - one that I'd been told was far too complicated for a novice to attempt, was on the air! I quickly hopped on my local repeater, a machine I had a difficult time hitting with my Diamond high gain HT antenna, and called out. Sure enough, I hit it just fine and received a full S9+ return. No one was on at the time, so I flipped over to a repeater on the opposite side of the county. I hit it and again received an S9+. This repeater was one I couldn't even manage to key up with my HT antenna and could barely even hear it, receiving S1 and S2 signals on a good day. Not only was my antenna working, but it was working well! A short time later a friend of mine hopped on the local repeater and we did some audio quality testing. He reported good signal there, so we flipped down to Simplex at 146.52MHz. There he immediately reported S9+50 from my 5 watts located in the valley where my house sits. We did some directional tests and found pretty much what was expected. Low side signals with high power from the front and a lower, but readable signal from the rear of the antenna. There's plenty more testing to be done on this antenna and plenty of documentation to write, but for now it's a usable antenna! Due to it's unique design, it's also quite the conversation piece so if you like to stand out, say at Field Day, this might be a good project for you! Thanks to all those who helped me - or tried to help me - along the way to the completion of my first antenna. I greatly appreciate it! By the way, yes I do plan on putting this antenna up on a tower at some point. The picture below is a temporary location for testing and temporary use until I can mount it on it's permanent home.
10m (20m) Dipole with a 1:1 balun September, 2012 Well, with the additional privileges offered by my recent upgrade to General, I figured I should probably get with the program and add some HF equipment to my shack. Of course, what's the use of having radios if I have no antennas to use them? First things first, a 10 meter dipole. Simple and efficient, the dipole is a good all-around antenna. Why 10 meters? Why not? I figured I'd start at the top and work my way down. No, actually 10m has just been "the place to be" on HF recently, with excellent conditions allowing for some serious DXing, so I thought it would be a great place to start. Besides, I have full access to that band now so I don't have to worry about watching my frequencies on it. Anyway, on to the build. I took down the Hentenna as I wasn't getting much use out of it in the location I had it in. This gave me the opportunity to use the large PVC pipe I had used for the "tower" in other aspects. I cut the PVC and started drilling. I installed a 239 connector and 18 ft of coax for the 1:1 balun in close turns. I've read a lot of different opinions about baluns including different lengths, number of turns, etc, so I picked one to try. Experimenting is half the fun, right? 16ft 3in of 16ga wire on each side soldered in with the coax, a complete wrap of electrical tape from top to bottom (both for weathering and asthetics - it looks better than plain PVC for the neighbors!) and some holes drilled for a mount hang at the top. Coax seal was used on all the exposed wire areas, effectively waterproofing the unit. Whalla! I have an antenna. I haven't yet got this antenna up and tested, but that's coming soon. Thanks to WA1GON for loaning me a radio to use. Hopefully I'll have a power supply by next week and we'll get this thing online! Looking forward to my first HF contact! I'm adding this a few months later. The stink of this project is that during my late night build I mis-measured this antenna. I doubled it so it was actually a 20m. On the up side, it still works great as a 20m and explains a lot. On the down side, I look like an idiot. What did we learn? Don't build antennas in the middle of the night! I have since also built a 10m dipole with a simple center connector without a balun. It works great too. Not much to say there so I won't add an extra post. 
Learning the HF Ropes December, 2012 So I've been on the air for a few months now and those QSL's are rolling in. Perhaps not as fast as I'd like, but that's my own fault. Seems there's never enough time in the day to do all my family duties and play radio too. Anyway, I do get to make a few here and there. More and more, however, I run into DX stations, and even some US stations, that only do Direct qsling. I have some photo paper and a QSL card program on the computer here so I print my own. They're nice enough, so it works. I have certainly learned not everyone responds to QSL's... or at least not in any rapid form. And I've also learned there are some problem people on the airways too. December 7th, 2012... about 15:30z (9:30a local) I ran across N4TAT on 20m. I was testing my radio with my newly repaired microphone and he was willing to shoot the breeze and give me some audio reports. It was a good conversation. I used to live in Georgia, where he was located, so we shared some thoughts and memories of the area. I later looked him up on QRZ and found no references to LoTW or eQSL, so I sent off a paper QSL since I needed GA toward a WAS award. About a week later I received my prestamped envelope back from him. I was hoping for his QSL card, but no... inside the envelope was my own card returned without a mark on it. I was disappointed, but I decided to figure out what went wrong. Did I do something wrong on the card, was he simply refusing to confirmed that particular card, or was there more to the story? I checked QRZ again and remembered I had found absolutely nothing on his page. Nothing as in he'd never updated it with any info at all. So I Googled his callsign. N4TAT... I quickly discovered his call sign appeared regularly in complaint forums, articles, blogs, and other such material as a "problem that must be dealt with by the FCC". Am I the only ham that's had a civil conversation with the guy? Wow. I also discovered he is tied in with the rest of the yahoos that use/abuse 14.313khz. I had learned within my first week about 14.313 and how it was considered the "badlands" of 20m. If there is a law, rule, or suggestion against it, those guys are usually doing it. Cursing, yelling, arguing, using more than legal power, retransmitting broadcast radio, etc. Those of you who are hams are shaking your heads right now saying, "Yes, we know this." So I quickly decided to call GA a wash and now I sit here debating whether or not I want to keep N4TAT in my log at all. But he didn't do anything to me or in my presence (earshot). I suppose I'll leave him in the log and just count it as another no-qsl contact. Ah well. It is a little disconcerting that I made contact with someone who is considered a "stalker" and "self-proclaimed child murderer", as I read in the many complaints and articles about him. But there's nothing I can do about it now. He can stalk all he wants, if that's his plan, but he'll find I'm not an easy target and I fight back. |
