What Happened To The Half Wave Dipole?
DICK WHETSTONE (AD4U)
on
August 14, 2008
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What Happened To The Half Wave Dipole Fed With Coax?
I am an “old timer” licensed in the 1960's, and I probably think like one. Back then “store bought” antennas were usually the exception rather than the rule, especially on bands below 20 meters.
When I read posts from HAMs asking why their G5RV does not work as expected, or how (and why) to install a radial system under a vertical, or why an inverted L does not work well, or what kind of “tuner” is needed to match a long wire, or why their OCF antenna has a high SWR, or how to feed a Super Duper Sky Buster, etc, I start to wonder.
When I read statements on this site and other sites about performance characteristics and claims made by some manufacturers of commercially produced HF antennas costing hundreds of dollars and the associated questions asked by HAMs who try to use them, I cannot help but think back to the good old days and wonder, “What ever happened to the half wavelength dipole (or the inverted V) fed with good quality 50 ohm coax?”
There are many reasons to use a half wave dipole on all bands, but especially on bands below 20 meters. Just a few reasons are listed below. I am sure there are many more.
A half wave dipole presents a very good impedance match for modern solid state transceivers.
A half wave dipole has a good operating bandwidth with respect to frequency.
A half wave dipole does not require an antenna “tuner” to work efficiently.
A half wave dipole does not require a radial system to work efficiently.
A half wave dipole does not require a balun to work efficiently.
A half wave dipole (properly measured and cut) does not require an “antenna analyzer” to get it working.
A half wave dipole does not require computer modeling software to get it designed and working.
A half wave dipole is relatively quiet on receive.
A half wave dipole can be built from scratch by the average HAM in half an hour or less.
A half wave dipole can be built from brand new components for much less than the cost of a typical commercial antenna.
A half wave dipole can be built (in a pinch) from scrap material, costing absolutely nothing.
A half wave dipole at typical height (especially below 20 meters) does not really “care” what direction it runs.
A half wave dipole cut for 40 meters will also work on 15 meters.
A half wave dipole cut for the upper end of 75 meters will also work on the lower end of 10 meters.
A half wave dipole, properly constructed and installed, will have little or no change in performance or SWR in the rain.
The legs of a half wave dipole can be (within reason) zigged and zagged to fit within the confines of a small lot without much (if any) noticeable loss in performance.
A half wave dipole is easily supported by trees or a simple pole and some nylon twine.
A half wave dipole will perform in the real world as well or better than most any single element commercially produced antenna, regardless of cost.
The more things change, the more they stay the same.
73 Dick AD4U
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RE: What Happened To The Half Wave Dipole?
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by W7ETA on August 14, 2008
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He he he.
One time, I had a new rig, but no coax, and no antenna. SO, I cut the ends off an extension cord, split the wires to around a half wave for 20 meters, tied a knot in it at that point, soldered a PL259 to the other end, taped it to the ceiling of the one story cabin I was in, loaded it up and made some Qs with my new rig (and antenna).
I try and remember than I had the advantage of starting on HF as a Novice--everybody knew the ops in the Novice sub-bands were just "Dumb Novices".
An advantage of the CW tests, at least for me, was that during the time it took me to increase my copy speed, I read a lot about ham radio principals, and asked a lot of questions.
My guess is that when new hams get HF priveleges, they gain access to 160, 80, 40, 30, 20, 17, 15, 12, 10 and 60 meters, and want some way to use their new ticket on all of those bands. By the time I got a General ticket, I had a lot of experience on HF--only had to worry about 80 and 40, which loaded on 15 and ran a used CB antenna on 10 meters for my first ticket. For me, making an antenna for 20 meters, my new band as a General, was easy and cheap.
Guess, if we can, we simply ans questions ops have so that they gain more knowledge, and can have more FUN.
73
Bob
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What Happened To The Half Wave Dipole?
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by KQ6XA on August 14, 2008
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.
"A half wave dipole is relatively quiet on receive."
I don't want a quiet antenna! I want a loud one :)
Seriously, though, there are a lot of hams out there using a dipole.
Good article!
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RE: What Happened To The Half Wave Dipole?
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by N7YA on August 14, 2008
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Hey, there we go!! at last someone is proclaiming the virtues of the good old simple halfwave DP...i have one, the ends are dropped making more of an Inverted V, but its still a 1/2 wave DP at heart.
All you need is the simple formula for cutting wire antennas to the frequency you like, get a good balun and coax, or a ladder line and a good tuner and off you go. Wrap it up, throw it in the car and hang it up at the campsite. Takes a few moments and a lot less stress and you are on the air. Granted, if you have the room, the patience and especially the money, go for a big 30 element super-dee-duper beam...go for it. But i dont....so half-waver it is.
I have 212 countries, all states, all but 2 zones, lots of IOTA's, etc...all with 100 watts and a half wave dipole. Its just a good, simple antenna that works. Thanks for the article.
73...Adam, N7YA
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What Happened To The Half Wave Dipole?
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by N9WB on August 14, 2008
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I am 59 years olde and have been a ham for over 30 years. I have trouble understanding why a person would purchase a dipole instead of making one themselves.
But then again, I cannot understand the concept of paying for TV or paying a dollar for a bottle of water.
I guess the youngsters have more money than time.
Vy 73, Walt N9WB
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Dipoles? I don't need...
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by K0RS on August 14, 2008
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...no steenking dipoles!
Last time I moved it was a couple of years before I was able to get around to putting up a tower with some of the Devil's own aluminum on top. Sooo...I picked up a 40 year old HyGain Hy-Tower, used, for hundred bucks. Yeah, it's got some of those nasty ol' radials on it. Radials...sorta like dipoles laying on the ground, but no supports or feedlines required. Pretty tough. Six or seven bands with one coax feedline, nice low angle response, no traps, no bandswitching, no tuners (unless you wanna cheat and add 60, 30, 17 and 12 meters, which it does quite nicely).
How many dipoles...and feedlines...would it take to replicate that performance? And how high would they have to be to get the low angle response, especially on the low bands? (Here's a hint: >>Prohibitively<< high.) Not to mention that most of 'em would require three, not two, supports because half-wave, coax-fed dipoles can't bear the weight of feedline. Oh, and dipoles *do* have nulls off the ends. Especially if they are high and in the clear. Right in the direction of that dx'pediton that you wanna work.
Hey, I don't hate dipoles...worked a lotta DX with them. Kerguelin Island on 20m, in fact. Damn near the antipodes from here...answered *my* CQ even!
But I do know this: I had dipoles up on forty and couldn't hear Japan. Hell, I *run* JA's on the Hy-Tower. And on 80 with a dipole, I frequently couldn't even hear the US East Coast from Colorado! With the Hy-Tower on eighty, Europe and Africa are no problem. The Pacific and JA are like my back yard.
Why don't I use dipoles? How about performance? And, uh, space. And cost. I put the Hy-Tower up myself without any $100 antenna launchers or climbing any damn trees. And did I mention performance?
Oh, and the Hy-Tower works passably well on six meters too. And not too bad on 162 mHz for monitoring NOAA wx radio. Maybe the best hundred bucks I ever spent!
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What Happened To The Half Wave Dipole?
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by N3QE on August 14, 2008
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Same thing that happened to single-band rigs :-).
Really, though, if you're going to bother to put up a dipole, you really should put up an all-band doublet, fed by ladder line and a tuner. The whole concept of bandwidth and SWR becomes completely irrelevant.
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What Happened To The Half Wave Dipole?
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by WW5AA on August 14, 2008
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I am also an "old timer". I discovered early on that their is no such thing as good coax if you do not have room for half a dozen dipoles. Yup, if you just want too work one band nothing beats a 1/2 wave dipole. However if you want to work multi-bands, whatever happened to the good old ladder line fed doublet. What usually is almost last on the list of priorities for most guys is to get that antenna high enough to work, and even further down on the list is a good receive system.
Waiting for fan dipole information (:-)
73 de Lindy
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RE: What Happened To The Half Wave Dipole?
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by M0JHA on August 14, 2008
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waiting for fan dipole information.. i like it.
cheap,easy and they work.
billy
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What Happened To The Half Wave Dipole?
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by AI4WM on August 14, 2008
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Well said Dick. I often wonder why some folks pay over 50 dollars or even more for a piece of wire and some insulators. It is not only a antenna that modern hams don't or won't build it is gear. Seems like if one does not have the latest and greatest rig with all kinds of automatic features costing thousands of dollars and fancy store bought antenna it's not ham radio.
Then as part of amateur radio that is why we have homebrewers and those who just buy and operate. I'd rather have more fun building and operating than just spending money, opening a box and putting something on the air.
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RE: What Happened To The Half Wave Dipole?
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by KY6R on August 14, 2008
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I have always loved the versatility of a ladder line fed doublet - through a very high end 4:1 balun and coax into the shack.
But when I raised my homebrewed 82' loaded ladder line fed doublet from 37' to 60' WOW - especially on 40 meters, I certainly understand what happens when you get a "simple" dipole up 1/2 wave.
I have also been able to take an array of simple 1/2 wave dipoles and build a K1WA array (3/8 wl fed dipoles sloping off my tower), and voila - I get the same F/B ratio and gain as any 2 element yagi - and it even eliminated the power line noise completely - for a fraction of what a store bought yagi would have cost.
I loved phased verticals, but like it even better getting the antennas WAY up high - where the wire almost becomes invisible.
And then there is the Bruce Array - fed like a vertical half wave dipole.
Wire rules!
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RE: What Happened To The Half Wave Dipole?
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by W4LGH on August 14, 2008
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You are 100% right. Been saying that for years. They are quick ,simple, and easy to build and put up. No tree climbing, just a simple slingshot, a 1oz weight, some mono-filament line, and you're in business. People say, they don't have room for all those antennas, and that's understandable, take your 1/2wave 80m dipole, throw in a few well made traps and you have a nice working multiband. If you make you traps right, the loss is not noticeable. Don't like traps, use multiple wires then, make it a fan dipole. Also ALL coax is NOT equal! Always use good quality coax like LMR-400, 9913, or CX-1318. Yes they cost a little more, but you'll get it back over time, and NO RF in the shack. (And that a real GOOD thing, more ways than one) You'll also get MOST of your power to the antenna. Ladder line is low loss, but its ugly, hard to conceal, and rain, ice and snow does effect it.
So , what happened to the 1/2wave dipole, nothing @ my shack! Have lots of them. (pun intended)!!!
Keep your grounds low, and your RF high..73
de W4LGH - Alan
http://www.w4lgh.com
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What Happened To The Half Wave Dipole?
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by NA4IT on August 14, 2008
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Nuthin' but Dipoles here!
40/75/160M in "fan" configuration.
60M dipole.
10/15/20M rotatable dipole made from a TA-33 driven element.
6M rigid tubing dipole.
Even the driven elements in the VHF / UHF beam are dipoles.
"J" dipoles for 2M, 220MHz, and 70CM.
LONG LIVE THE DIPOLES!!!
de NA4IT
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RE: What Happened To The Half Wave Dipole?
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by N2EY on August 14, 2008
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Two reasons the halfwave coax-fed dipole isn't more popular:
1) It's essentially a single-band HF antenna (except you can usually use a 40 meter dipole on 15). With nine HF/MF bands plus 160, that limits the appeal.
2) The lower you go in frequency, the more space is needed and the higher the supports need to be.
73 de Jim, N2EY
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RE: What Happened To The Half Wave Dipole?
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by N2UGB on August 14, 2008
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If it can be configured properly, a good ol' dipole is great. It is often a question of lot size, length and width (and HOA, and apartment restrictions), that is the determining factor for any antenna.
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RE: What Happened To The Half Wave Dipole?
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by WA8MEA on August 14, 2008
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1) It's essentially a single-band HF antenna (except you can usually use a 40 meter dipole on 15). With nine HF/MF bands plus 160, that limits the appeal.
--------------------------------------------------------
Not true, Jim....
(Warning! Shameless plug to come!)
Our little company has multi-band "fan" dipoles. (Either the Model 4 or Model 6)
Or....just use ONE dipole and adjust each reel when changing bands. It's not that hard to do and takes under five minutes!
I used one for a special event station and changed bands with a 1.1 to 1 match in minutes, going between 15, 20 and 40 meters.
I also use one for 40 meters and worked the Azores last year QRP on 40 meters. I adjust that antenna's length for the CW portion and the voice portion of 40 meters. I have the wire marked for each adjustment.
I'm not claiming dipoles are some sort of "special" antenna. However, they are dependable and the reason why we've expanded our product line of portable dipoles.
http://www.eham.net/reviews/detail/2363
My computer geek 15 year old son is currently making a new banner ad that flashes: "The Worlds Only FULL SIZE Portable Antenna!" This is to counter the nonsense from companies who use nothing more than mobile "sticks", shortened and configured in odd ways and then claim they are "dipoles".
73, Bill - WA8MEA
http://HamRadioFun.com
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What Happened To The Half Wave Dipole?
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by KB2DHG on August 14, 2008
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YEP the good ol dipole does indeed do the job...
I found this out recently when I had to move from a house to an apartment... Yea I miss my 3 element beam and tower but am doing OK with my G5RV...
If I had the room and permission, I would instead have dedicated 1/2 wave dipoles for 80 - 10 meters...
OH and yes it is far less expensive to build them yourself!
My G5RV is home brewed with the exception of the balun.
Nice article and very true!
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RE: What Happened To The Half Wave Dipole?
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by WA8MEA on August 14, 2008
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I guess the youngsters have more money than time.
Vy 73, Walt N9WB
------------------------------------------------------
It isn't so much youngsters, Walt. Remember, hams are not bringing in as many young people to the hobby as in the 1960's.
The reason why I started my business was exactly because of this reason. 20 years ago this January, I started selling plans for very simple, less-than-a-dozen-parts homebrew projects with ALL parts available at Rat Shack. I sold a ton o' plans at $3 a piece.
Then I started getting letters from people; "Would you please build one for me? I'm disabled." Or; "I live in a nursing home and we can't use soldering irons." But the CLINCHER was a letter from a lawyer; "I'd love to attempt to build this, but I DON'T HAVE THE TIME."
It was at that point I realized that there was a market for ready made, homebrew stuff. So the Peanut Whistle QRP transmitter and Tiny-Tenna active antenna were born!
I also remember something my dear grandfather told me when I was 18. I was going to take the day off from work and put a new muffler on my 1965 Ford Custom. My grandfather said; "Boy....why do you want to throw away $75 for a days pay, when you can take the car down and have Woody's Service Center put the muffler on for half a days wages?? That leaves you with the other half of the days pay to spend on girls this weekend!"
Smart man....
73, Bill - WA8MEA
http://HamRadioFun.com
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RE: What Happened To The Half Wave Dipole?
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by K0BG on August 14, 2008
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I'll take exception to one small item.
I decided to replace my auto-coupler driven doublet with a simple 80/40 trapped dipole. I had enough #12 copperweld on hand, and even had a chunk of Delrin tube to use for the traps. All I needed was a couple of 100 pF doorknob caps. To my amazement, I couldn't find any! I looked through a pile of them a pack-rat friend had, but no 100 pF ones. I found them on the internet, but they wanted $27.95 each! Heck with that noise! I bought a pair of ready-made traps from Unidilla, for $54. I ended up using the Delrin for the end insulators. I did wind a balun and mounted it inside a 3 inch PVC cap and used that for the center insulator. Except for the traps, I had everything I needed.
The moral? Sometimes, you have to buy something even though you didn't want to.
Alan, KØBG
www.k0bg.com
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What Happened To The Half Wave Dipole?
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by N5YPJ on August 14, 2008
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At 35 feet high and configured as an inverted Vee, I haven't found a dipole that overall will outdo my 6BTV, except on 80 meters where a dipole will outperform the vertical out to 600 miles or so. I wish, as I'm sure several other West Texas hams do, that we had a few trees tall enough to support dipoles to where they are more effective. I've read articles condemning the use of a vertical at frequencies above 80 meters and no doubt where the tall supports are available the the vertical may be a poor choice. At this QTH it gets QSOs in the log!
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RE: What Happened To The Half Wave Dipole?
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by WA8MEA on August 14, 2008
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The moral? Sometimes, you have to buy something even though you didn't want to.
-----------------------------------------------------
Alan:
This reminded me of the time we were selling homebrew plans advertising all parts available Rat Shack.
Well, there was one "part" that was readily available at ANY hometown hardware store. And that was a 1/8" wooden dowel for about 69 cents and used for a coil form.
I had some ham from Cleveland throw a fit over that! He wrote me a letter claiming he wasted three dollars on my plans because I had LIED! He claimed he didn't have a neighborhood hardware store! (Bull....) I think he was just frustrated trying to wind 45 turns around a 1/8 inch dowel. He probably was all thumbs, which some people are.
You meet all kinds in this business. I can't believe I've been at this for almost twenty years....
73, Bill - WA8MEA
http://HamRadioFun.com
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RE: What Happened To The Half Wave Dipole?
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by W9PMZ on August 14, 2008
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"I guess the youngsters have more money than time."
Remember, time is money. This is a universal constant!
If I earn $50/hour why would I spend an hour to go grab $20 of parts to make a $50 item? In other words I spent $70 to make a $50 dollar item.
Sometimes I'd rather spend time with my family rather to hole up in the basement by myself tinkering. It all depends on the needs at the time.
My biggest wonderment is why someone wants to commit to by Elecraft stuff, when the raw cost of some of their kits is on par with the cost of purchased material. If you calculate the cost to spending the time to construct the kit you double the cost.
Of course I will hear, but I like doing that... OK if that's how you want to cost your time.
73,
Carl - W9PMZ
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RE: What Happened To The Half Wave Dipole?
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by KG6WLS on August 14, 2008
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I'm sure this will stir some debate on coax vs. ladder/window line for a dipole.
What tickles me is there are some that will constantly find ways to build a multi-band dipole fed with coax. QST magazine August and September '08 shows two different configurations using pneumatics and relays. All this does is add more weight to the antenna system and invites failure.
Fan dipole w/ coax, or 450ohm line to a tuner. How simple can it be?
73
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What Happened To The Half Wave Dipole?
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by NT4XT on August 14, 2008
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I think lots of people are using half wave dipoles but, my theory is that with the advent of affordable and very good auto tuners, the single band, or half wave multiband stagger tuned wires have fallen by the wayside for G5RVs, simple whatever length center fed doublets, or OCFs.
Such non resonant antennas develope gain on higher bands, too.
I have never used a half wave dipole except on 40m and then, it was OCF. Why limit oneself. Or alternatively, two 102 foot doublets perpendicular will do wonders.
For QRO a non resonant G5RV is a very attractive viable option with a manual QRO tuner, or high power auto QRO tuner, and will do 80-10, minus 30. I wanted 30 so I turned it into a doublet, and for the most part gained 2 S-units on 30m.
So the simple coax fed half wave dipole with no tuner has fallen by the wayside perhaps, starting w/ the proliferation of affordable auto-tuners and Carolina Windoms, and then all the host of other OCF wires that followed. The cost is almost the same but you get more bands.
Some of the loudest regulars I hear on 40m use multi band doublets (window, twin-lead, or open wire tuned feeders).
So I think, the half wave dipole is still as popular as ever, they are just fed differently, and often resonant on only one band (quite often 20 or 40), but able to work efficiently and with gain on other bands.
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What Happened To The Half Wave Dipole?
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by N5YPJ on August 14, 2008
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I agree with NT4XT.
While these antennas do develop gain as you go higher in frequency, the question remains is it useful gain? If it's not going in the "right" direction it's wasted. I've run into that problem using ladder line fed doublets especially when configured as inverted vees.
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RE: What Happened To The Half Wave Dipole?
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by NT4XT on August 14, 2008
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That is true... 102' length flat, up 30 or more feet generally provides a good compromise between directions that provide gain (four main ones) and being simple, at least on 20m which is all that seems to practically matter these days for the average non beam ham.
A half wave dipole on it's resonant freq unless NVIS still has an issue of having a weaker signal off the ends.
The Inv Vee thing- yep. I'm no expert to be sure, but I do believe that depending on the angle of the Vee, will certainly diminish much gain.
But a flat-top G5RV length wire, efficiently fed via whatever method, sure does wonders on 20m in my experience, for such a simple antenna.
If an Inv Vee is the only option, well... at least it's multiband and mostly omnidirectional!
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What Happened To The Half Wave Dipole?
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by N0RZT on August 14, 2008
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Good morning,
In the last licensing class I taught a few months ago, I had the two pre-teen students in the class help me construct a 6m dipole. I started with an SO-239 chassis mount with a ring terminal soldered to the center pin and about eight feet of wire left over from an earlier project. I had them calculate the length of wire and cut it (suggesting that they cut it a little long since it's easier to remove the excess later than it is to add missing wire), and then they cut it in half. I crimped ring terminals to one end of each half. Using some small bolts, washers, and nuts, we then attached one half to the aforementioned center-pin ring terminal, and the other half to one of the mounting screw holes. I let them admire their work, and then I advanced the slide, showing the pool question "What is the approximate length, in inches, of a 6-meter 1/2 wavelength wire dipole antenna?"
If I'd thought of the idea more than an hour before class, I'd have pre-arranged a contact for the class using their new antenna. As it was, a few weeks later I strung it up for the June VHF QSO Party.
73,
Chris N0RZT/4
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RE: What Happened To The Half Wave Dipole?
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by K6AER on August 14, 2008
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Equating the cost of an antenna built by a manufacture versa what your time is worth is a straw man argument. The hobby is all about learning. I am willing to bet you don’t pay your wife for the meals she cooks versa eating out.
The real reason most new hams don’t make a dipole is they haven’t opened a ARRL handbook, ever. They memorized the answers and took a test.
Case in point… Every time a ham posts a simple question, like how to build a dipole, look at the class of license. Their all new extras.
In the old days a novice built much of what they used and learned about the technology along the way. When I took my general class exam in 1964 I not only had to draw the oscillator diagram but then had to explain what each component did in the circuit. I was not afforded the luxury of multiple guess answers. Today’s questions are multiple guess. Even a blind squirrel can find an acorn once in a while. Take the test enough times and you will pass.
NASA wants to return to the moon by 2020. I hope someone in India will be available to show them how. Science is hardly taught in today’s schools. There are no shop courses available. The public education system wants all their students to go to collage and be lawyers or hedge fund market managers. We don’t push education to turn out engineers any more.
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RE: What Happened To The Half Wave Dipole?
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by N4KC on August 14, 2008
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Nothing! That's what happened to the half-wave dipole. I talk to guys using them all the time. The problem is that we now would need SIX coax-fed dipoles to cover and be effective on all bands below 20 meters:
-- One for 160 (and that baby is 270 feet long, requiring some pretty good contortions on most lots)
-- One for the low end of 80/75 and one for the high end if you use the whole band and are ga-ga for resonance
-- One for 60 meters
-- One for 40 meters
-- One for 30 meters
Of course, the solution, as already mentioned, is the dipole fed with parallel-conductor feedline, not coax, and using a decent matching system. There is no need to worship at the altar of resonance. A single half-wave dipole cut for the lowest band you intend to use, fed with ladder line or open wire feedline, can be a very effective antenna for all those bands mentioned above and more.
Such an antenna is great for all the reasons stated in the article (exception: rain and its effect on ladder line is greatly overstated), especially its simplicity and inexpensiveness. Using a low-loss feedline and matching device to tune the entire system makes it multi-band. It will also exhibit gain on higher frequencies (primarily in two directions).
Certainly there are other options -- verticals, fan dipoles, loops (one of my favorites) -- but, as noted, the simple dipole is within the reach of most hams, regardless of technical ability or cash-on-hand.
Don N4KC
www.n4kc.com
www.n4kc.blogspot.com
www.donkeith.com
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RE: What Happened To The Half Wave Dipole?
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by N3JBH on August 14, 2008
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A half wave dipole does not require a balun. I can not believe my eyes!!! That is sacrilege.
Life with out a Balun is not worth living. :)
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RE: What Happened To The Half Wave Dipole?
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by WA8MEA on August 14, 2008
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A half wave dipole does not require a balun. I can not believe my eyes!!! That is sacrilege.
Life with out a Balun is not worth living. :)
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I know that, and you know that. However, you would NOT believe the number of oldtimers who wanted to know when we were going to make a version of our portable dipole WITH BALUNS! I remember as far back as 1970, the VETERAN hams at Purchase Radio Supply in Ann Arbor, Michigan told my dad and I that we needed to use a balun! How long ago did this urban legend originate????
I tried to reason with these balun customers, explaining that they don't need one! But it goes in one ear and out the other. They just weren't going to order a portable antenna until we put baluns on them!
So as I stated on the website, I gave some of the customers what they asked for: a balun. Some swear by 'em, while others of us sear at 'em!
Within 24 hours of putting those new portable dipoles w/ baluns up on our website, the first orders for them rolled in. I was amazed, astounded, shocked....
73, Bill - WA8MEA
http://HamRadioFun.com
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RE: What Happened To The Half Wave Dipole?
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by W4VR on August 14, 2008
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I've been using coaxial-fed horizontal dipoles for years. When I need more gain I simply add a director or reflector, or both.
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What Happened To Hams' Curious Nature?
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by K4RAF on August 14, 2008
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To me, this is a sign of the culture we live with in 2008...
I started listening to SW broadcasts at age 10, there was no internet...
I grew up with a quest or better described as a fascination to learn about, understand & build antennas from 10KHz-10GHz by asking for information from stations, buying books & magazines & talking to older radio enthusiasts (not necessarily hams either, but SWLs too)... There was no internet...
When I took my tests before the FCC examiners (early 1980's), you had to know/be fluent in antenna theory, do calculations without programmable calculators & that was true of both amateur & general radiotelephone tests. There was no internet, but Usenet & BBSs were around, still no internet...
After college, I sought to work in RF engineering, specializing in field support, by designing & building antenna systems up to 30GHz... I have seen a reduction in the number of hams in the RF business over the last 15 years.
In 2008, I still build any antennas for HF but VHF/UHF/SHF frequencies, I have become a consumer, especially for 802.11 & ISM applications. Through the years, I have lost many radio active hams to the internet, which has swelled in its' looming presence in everyday society. I now work in wireless systems design & RF to fiber bandwidth solutions. I had to evolve from working in broadcast engineering, to cellular construction & design, to wireless broadband... Times have changed because of the internet, even for me.
After 26 years in ham radio, I look around & wonder where are those who want to know why an antenna is what it is... What frequency is it on? What does "it" do... I don't see them without a chat window open on their (parents) smartphone... My point is people have become too lazy to learn the dipole formula, let alone solder wires together, in today's ham radio. While the re is blame to go around, the reasons for getting into the "hobby" come from one source, who seeks to both define & commercialize ham radio. I'll give you a hint:
"We Can Do That?"
Ummm, no we can't if you look around, not even close... because of your definition of "knowledge" & "tests"... but rule knowledge is not a direct replacement for 468/frequency in MHz!!! You do not stand for technical knowledge to be retained in testing but you will take PayPal for a matching EMCOMM whistle & orange vest with your emblem on it?
Knowledge is what you make it but good luck to you all on recruiting those crumb crunchers to be the next brain trust of antenna engineers! G5RV proved that Darwin was right... Survival of the Strongest involves inhaling rosin smoke & ladderline!!!
Raf
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Where have all the flowers gone?
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by WB2WIK on August 14, 2008
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I sometimes attend local radio club meetings and am astonished at the dearth of knowledge...it's truly sad.
Nobody picks up a book to read about our stuff.
I've had hams tell me they can't figure out how to get a coaxial cable inside their home, from outside. I pick up an electric drill with a 1/2" masonry bit and say, "How about this method?" and they're shocked -- "You can drill a hole through the wall?"
I'm not kidding.
I've had hams ask me about a "Halfway Dipole."
I say, "Halfway to what?" and they respond, "Not sure, just heard the term and wondered what it meant."
:-(
WB2WIK/6
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RE: Where have all the flowers gone?
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by N6AJR on August 14, 2008
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I know you are looking for this.. HI hi
Bye the way, none of this is mine, Its just stuff I pulled from here and there. thanks to all the folks with the great sites. this is My take on the multi-band, single feed wire dipole ( but fan dipole is easier to type. a true fan dipole is also called similar to a cage dipole and has 3 or 4 wires of different lengths on the same band , like a 64 foot , 66 foot and 68 foot double leg wires on the same feed to give wider bandwidth, but bottom line, they are cheap, easy to build, and they work..
http://www.ku4ay.net/dipole.html
http://www.qsl.net/kd7rem/antdipole.htm
http://www.hamuniverse.com/multidipole.html
http://www.angelfire.com/nb/ni4l/ni4ldipole.html
http://www.arrl.org/tis/info/pdf/9611073.pdf
http://www.geocities.com/n2uhc/2banddipole.html
http://www.qsl.net/na4it/fandipole.html
by N3JBH on October 12, 2006
FAN DIPOLE OR MULTIPLE BAND DIPOLE SPECS:
(Each leg is shown in length so you will need two legs.)
10 METERS = 8'4"
12 METERS = 9'5"
15 METERS = 11'1"
17 METERS = 12'10"
20 METERS = 16'8"
30 METERS = 23'2"
40 METERS = 32'9"
60 METERS = 43'7"
75 METERS = 60'9"
80 METERS = 65'6"
160 METERS = 123'5"
137 KHZ = 1708'1"
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RE: Where have all the flowers gone?
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by N6AJR on August 14, 2008
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I know you are looking for this.. HI hi
Bye the way, none of this is mine, Its just stuff I pulled from here and there. thanks to all the folks with the great sites. this is My take on the multi-band, single feed wire dipole ( but fan dipole is easier to type. a true fan dipole is also called similar to a cage dipole and has 3 or 4 wires of different lengths on the same band , like a 64 foot , 66 foot and 68 foot double leg wires on the same feed to give wider bandwidth, but bottom line, they are cheap, easy to build, and they work..
http://www.ku4ay.net/dipole.html
http://www.qsl.net/kd7rem/antdipole.htm
http://www.hamuniverse.com/multidipole.html
http://www.angelfire.com/nb/ni4l/ni4ldipole.html
http://www.arrl.org/tis/info/pdf/9611073.pdf
http://www.geocities.com/n2uhc/2banddipole.html
http://www.qsl.net/na4it/fandipole.html
by N3JBH on October 12, 2006
FAN DIPOLE OR MULTIPLE BAND DIPOLE SPECS:
(Each leg is shown in length so you will need two legs.)
10 METERS = 8'4"
12 METERS = 9'5"
15 METERS = 11'1"
17 METERS = 12'10"
20 METERS = 16'8"
30 METERS = 23'2"
40 METERS = 32'9"
60 METERS = 43'7"
75 METERS = 60'9"
80 METERS = 65'6"
160 METERS = 123'5"
137 KHZ = 1708'1"
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RE: Where have all the flowers gone?
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by N3OX on August 14, 2008
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N3QE writes:
"
Really, though, if you're going to bother to put up a dipole, you really should put up an all-band doublet, fed by ladder line and a tuner. The whole concept of bandwidth and SWR becomes completely irrelevant"
I don't necessarily agree. They can be great antennas, but what happens to people is that they end up having a hard time routing the feedline into the house, or their tuner won't match it, and they end up with a lossier and/or more confusing situation than would best serve their needs at the moment.
Then they spend a bunch of time trying to troubleshoot their system instead of working some DX.
SWR doesn't become *completely* irrelevant when you put up your ladder line fed doublet, it becomes *nearly* irrelevant on most bands... until your tuner arcs over or you decide to "just run 15 feet of coax" out of the basement to some "4:1 balun" outside.
Or they're using a cheap tuner... I had an MFJ "300W" tuner fail when I was running 100W on 80m RTTY into a very high impedance antenna. The styrene coil supports melted and the coil shorted out. It might have only been 2dB or 3dB loss in the coil, but until I melted it, I would have never noticed that I was dropping that power in the tuner.
This is especially true if they overestimate the ability of the tuner to make the antenna radiate efficiently. That seventy foot long doublet doesn't actually work well at all on 80m, even if it "loads up"
- - - - - -
Guess my point is, it's *very* hard to do a halfwave resonant dipole "wrong," where there are dozens of easy ways to make a ladderline + random doublet system worse than a good one.
Dan
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RE: Where have all the flowers gone?
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by N4BFD on August 14, 2008
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You would be a lot better off to run that balance line into a GOOD 1:1 choke balun, with as short as run of coax to the tuner as possible.
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RE: Where have all the flowers gone?
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by KF4HR on August 14, 2008
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"What happened to the half-wave dipole?"
Hummm, not sure. But my two Windom antennas are installed out in my back yard facing north/south and east/west (selectable). I figured why put up a standard dipole when an off-center feed dipole provides more frequency advantages?
KF4HR
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What Happened To The Half Wave Dipole?
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by NT4XT on August 14, 2008
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Sweet.
I think what happened to the half wave dipole was the G5RV, Carolina Windom, and other OCF's that followed- now everyone's making an intended to be fed by coax OCF, even Alpha Delta though I can't seem to see it on their web site.
I was wondering when this thread was gg to turn into the great debate of which balun to use, how much loss is really noticeable on the receiving end because of the balun+tuner... etc.
For me the question of which balun turned into what's the complex impedance on the bands I use most, at THE end of the window line- and can I make it better by changing the length, if so by how much, do I want the Z that connects to the TUNER to be slightly inductive or capacitive to minimize loss in WHATEVER kind of tuner/balun or balun/tuner I have, and all that.
Still though back to what happened to the half wave dipole? Well, a G5RV is deceptively simple but works great... a 40m coax fed perfectly resonant half wave dipole system fed with coax will work how on 20m? Because a G5RV for as simple as it is, works like gangbusters on 20m quite often.
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RE: What Happened To The Half Wave Dipole?
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by KC2OYZ on August 14, 2008
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In many cases (like mine for example) it depends on your QTH. For me, wires are really the only viable option.
And yes, the idea of buying a dipole seems rather silly to me - for the cost of one commercial dipole you can buy enough wire, insultors and connectors to last you for the duration of your on-the-air career.
Besides, I always thought hams were supposed to be do it yourself guys - nowadays there are some hams who seem to think that the more fancy gear they can buy, the better their station is and the more important they are. I've got nothing against them if that's what they like, but I think they're missing the whole point of the hobby.
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What Happened To The Half Wave Dipole?
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by K5EAG on August 14, 2008
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I wonder too. I first got my Novice ticket back in 1958 when all I had to get on the air was an old Army Surplus ARC/5 50 watt, crystal controlled transmitter, and old Hallicrafters receiver, surplus straight key and yes, a home brew dipole cut for 40 meters. I only had one crystal for the Novice CW band on 40 meters. Later I was able to purchase a crystal for 80, 15 and 10 meters. Back then Novices could not operate on 20 meters CW. I had no balun, no SWR meter, Antenna Analyzer or Field Strength Meters. Just some copper wire, a piece of Plastic or Plexiglass for my center insulater and soldered on a piece of RG8 coax and strung it up on a pole at one end of the roof and the other end up in a tree in the back yard. The dipole was up about 15 feet and ran East/West, but I was able to work stations all over the USA and even some DX. I had fun making my dipoles and still to this day make my own. I even built my first 15 meter beam out of 1x4 lumber and bamboo fishing poles with 300 ohm TV twin-lead taped to the bamboo poles and mounted atop a 25 foot pole. No rotator, just metal rods welded to the bottom section of the pole so I could run outside and twist the pole to rotate it. Worked stations all over the world back then on 15 meters and 50 watts. No fancy store bought stuff.....I was a poor 14 year old West Texas boy with a great Hobby and a desire to build things and get on the air. That was 50 years ago....call sign was KN5TOY....
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What Happened To The Half Wave Dipole?
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by G0GQK on August 14, 2008
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I can't believe what I'm reading ! Usually when someone sends in an article half of America writes in to say its all garbage.! One little thing which wasn't mentioned is the efficiency of a half wave dipole, some say its about 90%, I just believe what they say.
What I cannot understand is why the G5RV antenna became so popular in the US. Was it because it's cheap to make, can be sold at hamfests and fits easily into a plastic bag ? Was it because G5RV seems to be an exotic sort of British call sign ? People may have noticed that there were were few G5 calls issued in Britain so they think this man was a Guroooooo !
Something that is never mentioned is that resonant dipoles can be made with 300 ohm ribbon feed. I've seen a design with four bands,10, 15, 20 and 40 and fed with 50 ohm coax. It will have to be supported with cord but for anyone who wants four bands and resonant without using an ATU this is the way to do it
Mel G0GQK
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RE: What Happened To The Half Wave Dipole?
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by W3ML on August 14, 2008
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I, too, am an old ham. 30 years next year. My Christmas present from my non-ham son last year was a 1000 foot spool of wire.
He said here go make some new dipoles.
Even he knows all you need is a dipole to make good contacts.
John
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What Happened To The Half Wave Dipole?
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by W9GDH on August 14, 2008
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It follows the KISS rule.
And it makes a very good Ecom antenna.
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RE: What Happened To The Half Wave Dipole?
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by QRZDXR2 on August 14, 2008
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A half wave dipole does not require a balun to work efficiently.
-----------------------------------------
really!!!
no. They work better when you have the whole dipole antenna acting as a radiator.
Think about it for a min. If the coax is grounded on the shielding at the radio, the radio is grounded to the ground, and the shielding is soldered to one half of the dipole what do you think the effect is having one half of the antenna grounded but up in the sky? The half connected to the center conductor is going to have a reactance with all things ground because of this. Thus you have a unbalanced system that can raise hell, hate and discontent with the neighbors next door. Balance it out by placeing a balun in the center of the dipole antenna and like magic the interfearance with them goes away most of the time.
Put a balun in the middle of the dipole and your pattern changes to a much better antenna.
that is the only change I would add to your article. Otherwise the old dipole is a tried and true antenna that is the basis of all others to match and be rated by. But, you do have to have the room to put it up in the air for the lower bands. some neighbors just don't like to see things the same way as hams do.
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RE: What Happened To The Half Wave Dipole?
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by QRZDXR2 on August 14, 2008
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"I guess the youngsters have more money than time."
Remember, time is money. This is a universal constant!
If I earn $50/hour why would I spend an hour to go grab $20 of parts to make a $50 item? In other words I spent $70 to make a $50 dollar item.
Sometimes I'd rather spend time with my family rather to hole up in the basement by myself tinkering. It all depends on the needs at the time.
My biggest wonderment is why someone wants to commit to by Elecraft stuff, when the raw cost of some of their kits is on par with the cost of purchased material. If you calculate the cost to spending the time to construct the kit you double the cost.
Of course I will hear
Carl - W9PMZ
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Like so many others (no punn intended) you miss the boat Carl. Its not about the money it about the intellegence and gratification of making something... and making it work as good or better.
If you go by your own ideas, why get a ham radio, license and all. Its a waist of time and money according to you. A cell phone would be much more economical to use. So why are you a ham? Why do you go out and buy a $1000.00 radio when you can get a cell phone that does even more for only $29.95. By your own words then ham radio is not cost effective. (one of the major reasion I guess the newbies didn't like code too) Its too bad that accomplishments and pride are not valued items. Maybe that is what is happeing to america today that years earlier wasn't. The new generation is buy it... where the old was into taking something that was discarded and turned it into something that was useful and enjoyable. (maybe that is why today society is fighting global dumping problems) Without a price tag attached for time and effort. After all this is supposed to be a hobby and not a business, as I am reading.
Sounds like your trying to convence yourself of the economics of being right while justifying your ham license as to being one of the boys.
Can't have it both ways dude.
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RE: Where have all the flowers gone?
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by QRZDXR2 on August 14, 2008
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I've had hams ask me about a "Halfway Dipole."
I say, "Halfway to what?" and they respond, "Not sure, just heard the term and wondered what it meant."
-----------------------------------------------------
sad thing is that they were licensed as new extra class hams....
Intellegence is something the other guy has ...according to them. They look at the guy as a nurd or geek for making his own. However, they still buy his products for elevated prices only because they are dumb or stupid (their choice) Guess who gets rich selling stuff to the newbies when he takes his stuff into production.
Hams... used to be... walking talking thinking professionals. Money has turned them into... (you fill in the blanks) Most kids today wait along side the road of life for the auto club to come change their flat tire... instead of doing it themselves... and getting on down the road... go figure...
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RE: What Happened To The Half Wave Dipole?
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by K6CRC on August 14, 2008
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Why is it that EVERY Forum ends up with three comments from a small number of hams--
I haven't got any money so I have to (fill in the item you have to scrounge or build), if you BUY one then you are stupid and lazy
Young people are stupid and lazy.
If you find CW something you don't like, you are stupid and lazy.
So, you call anyone who is successful in life and values time MORE than money stupid. You call any one who is different than you lazy. You call anyone who was born after 1985 both names.
Then, you wonder why 75 meters is full of low class old guys who cannot afford to pay for anything you want to sell.
Amazing...
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RE: What Happened To The Half Wave Dipole?
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by N5YPJ on August 14, 2008
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W9PMZ,
I can relate with some of what wrote. In my case family juts didn't allow for much building except some antennas. As a single man I built and enjoyed a few kits and looked forward to projects like that. Now my kids are getting a little less dependent on me and it's a lot harder to find components, at least IMO - QTH is 150 miles to nearest electronic supply house, once Radio Shack dropped coax - 150 miles to buy any. I had looked forward to a couple of Ramsey kits but the FM xcvrs are now out of production.
Heathkit - where art thou?
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RE: What Happened To The Half Wave Dipole?
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by WN9DDV on August 14, 2008
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I agree with the gentleman about the OFC dipole. Resonate on all bands without a tuner and receives and gets out well. Also don't forget about the half square antenna. It also is a dipole and has an extremely low angel of radiation.
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RE: What Happened To The Half Wave Dipole?
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by KC2OYZ on August 14, 2008
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K6CRC - "cannot afford to pay for anything you want to sell"
Ever consider the possibility that those 'low class old guys' know that you threw away your money on something that you're now trying to unload on them?
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RE: What Happened To The Half Wave Dipole?
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by K0EWS on August 14, 2008
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Wire antennas are great. If I had the room for 9 different dipoles, I'd put one up for every band. Some day I just might. My old field day group used nothing but half wave dipoles. Installed high enough, they were very hard to beat.
In the meantime, I use an all band doublet, 44 feet for 10-40 meters, and 88 feet for 20-80 meters, Fed with twinlead. The 44 and 88 foot doublets, fed with twinlead are wonderful as the radiation patterns on them are very predictable, broadside to the antenna. launched high enough, and fed with a tuner, they do a great job, and act just like a half wave dipole.
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RE: What Happened To The Half Wave Dipole?
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by KC2WI on August 14, 2008
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Dipoles are great, but for a multiband antenna I like my G5RV.
Some people think they are junk. Yes I know they are a compromise, compared to a resonant dipole. But if you don't have lots of room and/or supports for multiple antennas, and can't get open wire/ladder line into the shack, the G5RV is a reasonable compromise. I don't expect a G5RV to have low SWR anywhere. (Although the one 15' my roof shows low SWR at the radio on 40 M, don't know why. Reflections from the metal roof, "detuning" because one end is tangled in tree branches??? Since I like use 40 a lot an 20 not much, I'm not complaining.)
I'd rather feed the "dipole" element with ladder line all the way to a balenced line tuner in the shack, but that's not an option at my present location, so I accept some coax loss.
What I'd really like to see available is a remote true balanced line autotuner (not just one with a balun slapped on the end). Since no such thing is available, I'm probably going to try putting a standard autotuner with good balun betwen the coax and balanced line and see how that works out.
As far as building vs. buying, it's true time is money and if you don't have the parts in your junk box it can be a pain and the coax, ladder line, connectors can cost almost as much as the whole prebuilt antenna. But everyone should try building one or two simple antennas. Besides, if you consider the time spent building an antenna a waste, then what about all the time you waste talking on the radio? Building stuff is just as much a valid part of ham radio as actually operating.
G5RV's are sooo simple and cheap to make, and versatile to use when you can't put up a better antenna. Besides, it's really a kick to make contacts on an antenna you made yourself, at little or no out-of-pocket cost. Just about anyone can find the materials for free, or almost. About 102 feet of wire for the doublet. Any insulating material for the center insulator (wood works). If you don't have ladder line, make your own open wire line or use good quality TV twinlead. (I know, not perfect but it works.) Use any old coax. Grab a hunk of 75 ohm TV coax, doesn't really matter since the "feed point" isn't 50 ohms and you're going to use a tuner anyway. Wind several turns around a piece of plastic pipe or bottle for a choke balun where it connects to the balanced line. Other than maybe the PL-259, everything you need can probably be found in the neighborhood garage sales (or garbage even...) if it isn't in your junk box.
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RE: What Happened To The Half Wave Dipole?
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by KE5MXA on August 14, 2008
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I have had my license for almost a year and a half. in the air are three 1/2 wave (home built)dipoles 80,40,and 20. They are not at the greatest heights but they work for now. The only reason I dont have more dipoles in the air is time and space. 80m loop is in the works. My first 2m antenna was made in about 15 min from a scrap piece of 8x and romex. i used it until i got a marine vertical (for free)that covers 2m and works better plus a 125mph wind rating hi hi. There is still much i dont know about our hobby, but i am always learning. the only killer is time... not enough to go around.
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RE: What Happened To The Half Wave Dipole?
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by NI0C on August 14, 2008
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The question, "what happened to the half wave dipole?," could be translated to read: "what happened to large lots with big trees and tolerant neighbors?"
Like K0RS, I use vertical antennas because they work well and take up so little space. My vertical dipoles don't require any radials, yet they yield results comparable to horizontal dipoles deployed at heights impractical on my property.
73,
Chuck NI0C
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RE: What Happened To The Half Wave Dipole?
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by N4BFD on August 14, 2008
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Why bother to run a dipole in the first place, if your are going to put up a 40 or 80 meter dipole may as well make it off center fed with the right balun, with a good 1:1 choke or good current balun and call it a day. Low SWR dips on just about all the bands. Why make a single band antenna when you can put just a bit of extra work in and have a multi band antenna in the same space?
Of course the best way to go is put up a center-fed balance line fed whatever.. but if you can't swing that, at least go the OCF route if you have to use coax all the way to the rig.
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RE: What Happened To The Half Wave Dipole?
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by K0EWS on August 14, 2008
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<<<Dipoles are great, but for a multiband antenna I like my G5RV.
Some people think they are junk. Yes I know they are a compromise, compared to a resonant dipole. But if you don't have lots of room and/or supports for multiple antennas, and can't get open wire/ladder line into the shack, the G5RV is a reasonable compromise. >>>
The G5RV is a great antenna! I have one. I use it, and like it. For 80 and 40 meters it does a nice job, but it really shines on 20 meters. Of course, I have it about 40 feet up, and in a flat top configuration. The lobes I get give me some very nice gain for DX on 20 meters. The antenna gets a bad rap because some people expect it to do all things equally well. It doesn't. Someone labled it as a "compromise" antenna, and it's really not. Still, for some things, it's great.
What I specifically don't like about the G5RV, compared to the 44 foot and 88 foot doublet, is the radiation pattern. It switches for each and every band. The elevations and radiation patterns are all over the place. A 44 and 88 foot doublet fed with ladder line or twin lead have a nice stable, broadside radiation pattern, and the same pattern on every band. What one could do is run some big coax out of the shack and use a balun to the twin-lead. I've done this, and it works if you don't make the coax too long.
Top of my list of wire antennas is the half wave dipole. If I can't have one for every band, the next best thing is an all band doublet, fed with open wire, or twin-lead.
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RE: What Happened To The Half Wave Dipole?
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by KG6WOU on August 15, 2008
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I'm a reasonably new Amateur, but it seems to me that antenna become 'fashionable' and go in and out of style for a variety of reasons.
Examples:
Co-Ax cable itself is a reasonably new innovation, or at least it's popularity seems to originate from the end of WWII. At that point, resonant antenna became more important, which I suspect made resonant antenna more popular both for line loss and ease of matching.
So the open feed line gets a bit neglected, now it's coming back as we remember that it has many virtues when trying to address high swr conditions, and as pointed out, handy when you need to manage 10 HF bands
At one time, none of us would be contemplating anything like the Yagi-Uday array [beams] we currently buy, we would be building V's or Rhombics or various giant wire gain antennas like the lazy H, stacked dipoles and the variety of land intensive wire antenna array. All of it fed with open wire feed line.
Of course, does anyone use a flat-top with 6-8 parallel radiating wires anymore?
"Omni mutantur et nos mutamuer en illis" Times change, and we change with them....
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RE: What Happened To The Half Wave Dipole?
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by DJ0RD on August 15, 2008
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I use a vertical because my "yard" is approximately 20 feet by 20 feet in a condominium complex. The neighbors would panic if they saw a dipole strung across the "neutral territory".
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RE: What Happened To The Half Wave Dipole?
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by W9PMZ on August 15, 2008
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"Sounds like your trying to convence yourself of the economics of being right while justifying your ham license as to being one of the boys. "
I knew this was coming.........
You really didn't listen to what I said. I gave you tinkerers holed up in your shacks an out. It's not about economics, it's about personal choices.
From my point of view kit building was a way to save money. I suspect for most it was never about under standing how the equipment really worked (as a side note one respondent cracked me up as to his abilities when he talked about melting a coil in a MFJ tuner, connecting the tuner to a hi Z antenna, didn't he read the manual?); it was about getting on the air and talking to people! At least in the early 70s that what is was for me. I suspect most learning went on because in kit building,
1. Couldn't figure out the on knob,
2. Couldn't solder,
3. Couldn't follow instructions,
It was only then that you learned how to troubleshoot electronics from a schematic. At this point how may people understood really what was going on in a mixer?
Sure, I built my share of Heathkits; but it wasn't until I finished engineering school that I really understood the design and engineering behind the equipment. And I am still learning today! But I get nothing out of soldering wires and installing them on an insulator to see how it works.
All of you antenna builders; are you an Edison or Tesla?
Right now my priorities are my family and work and radio is a distant priority.
73,
Carl W9PMZ
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RE: What Happened To The Half Wave Dipole?
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by KY6R on August 15, 2008
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I think a "Halfway Dipole" is a vertical with no radials - or an inverted L - or someone's attempt at a dipole where they either had a few too many beers before they plugged in the soldering iron.
Or maybe, they used 234/freq thinking that was the formula for a "Half Wave Dipole".
;~>
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What Happened To The Half Wave Dipole?
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by W3NRL on August 15, 2008
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Dick ADU4, yes your right!!!
love my wire antennas and i make all my antennas.
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RE: What Happened To The Half Wave Dipole?
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by W4LGH on August 15, 2008
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W9PMZ said..."All of you antenna builders; are you an Edison or Tesla?"
Definitely Tesla.. Edison was a FAKE! His assistants did all the discoveries and the work. Edison ran to the patient office and put his name on it. Edison was the "Martha Stewart" of the electronics world.
Also if the length of the 1/2wave dipole doesn't fit your lot.... Use ladder line as a folded dipole and you cut the length in 1/2!! So that 130' 1/2wave 80M dipole just became 65 feet total length! Not quite as good as stretching it out fully, but it will get the job done nicely. Just short the ends, and feed one side of it. Great bandwidth too! Now feed it with an SGC autotuner and you have a effective multiband antenna! Used this combo in my attic, when I lived in a condo for years. Also put it back up in the attic of my house, as a backup HF antenna!
73 de W4LGH - Alan
http://www.w4lgh.com
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RE: What Happened To The Half Wave Dipole?
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by W5ESE on August 15, 2008
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> Also if the length of the 1/2wave dipole doesn't fit
> your lot.... Use ladder line as a folded dipole and
> you cut the length in 1/2!! So that 130' 1/2wave 80M
> dipole just became 65 feet total length! Not quite
> as good as stretching it out fully, but it will get
> the job done nicely. Just short the ends, and feed
> one side of it.
I don't think this is right. A folded dipole is still
a half wavelength long. The advantage is somewhat
wider bandwidth and an impedance of ~300 ohms. So
you can feed it with cheap 300 ohm line instead of
more expensive coax.
But the length is the same as a standard half wave
dipole.
73
Scott
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RE: What Happened To The Half Wave Dipole?
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by AC7CW on August 15, 2008
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Yessss.... dipoles are easy and fun. I had a single band heathkit rig for 20 so I went all out building an inverted vee, I got the center up 32 feet with spar varnished wood and guys at the center and the top and the antenna itself was half of the top guying....... hey, there's another thing to add to the list of what's good about dipoles, they are partially self guying in the inverted vee configuration!!
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RE: What Happened To The Half Wave Dipole?
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by W1XZ on August 15, 2008
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>>Remember, time is money. This is a universal constant!
If I earn $50/hour why would I spend an hour to go grab $20 of parts to make a $50 item? In other words I spent $70 to make a $50 dollar item.<<
It would probably be more like $20 per hour...or less on average. Would you work 3 or 4 hours to buy for something you could construct for less than one hour's toil?
As far as time goes, by the time it takes to call the company or order on line, wait for arrival, open and inspect the contents, and put that shiny new faux G5RV up you could be enjoying a nice dipole that you have the satisfaction of building yourself.
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RE: What Happened To The Half Wave Dipole?
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by W6JAK on August 15, 2008
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Regarding what your time is worth...I my case I would not be building any antennas while at work. I build antennas during my spare time, when I am not making any money, so my salary or wage/hour is irrelevant. Discussions on what your time is worth are relevant only if you take unpaid time off work to build antennas or build them while on the job. The latter case is not an option for most people, as they would be soon unemployed.
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RE: What Happened To The Half Wave Dipole?
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by K5END on August 15, 2008
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W5LGH, Alan
True words you speak regarding Edison.
He was a businessman. Nothing more.
73
K5END
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RE: What Happened To The Half Wave Dipole?
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by K5END on August 15, 2008
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quote, "What I cannot understand is why the G5RV antenna became so popular in the US."
Mel,
I call that the "Jaguar" syndrome.
:-)
73
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What Happened To The Half Wave Dipole?
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by KI4TZX on August 15, 2008
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New guy here...
Maybe I just like making things( I do ) but I see no reason to buy something that may or may not work the way I want, when I can make one and try it. In the year and a half or so I have been in this hobby I have made a variety of antennas, the ones that work the way they should ..stay. Otherwise the wire gets turned into something else. At 50 years old I guess I am in between the build everything and the buy everything groups.
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RE: What Happened To The Half Wave Dipole?
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by W9JCM on August 15, 2008
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A wire is a wire is a wire. Unless you plan on putting it up at 70 feet flat top a wire will only give you so much half wave dipole or whatever. Do your homework save your dollars and get yourself something directional with some gain if you are serious about dx. Other wise a wire will work just fine. As they say its all in the antenna.
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RE: What Happened To The Half Wave Dipole?
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by QRZDXR2 on August 15, 2008
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W9PMZ on August 14, 2008 "I guess the youngsters have more money than time."
Remember, time is money. This is a universal constant!
If I earn $50/hour why would I spend an hour to go grab $20 of parts to make a $50 item? In other words I spent $70 to make a $50 dollar item.
Sometimes I'd rather spend time with my family rather to hole up in the basement by myself tinkering. It all depends on the needs at the time.
My biggest wonderment is why someone wants to commit to by Elecraft stuff, when the raw cost of some of their kits is on par with the cost of purchased material. If you calculate the cost to spending the time to construct the kit you double the cost.
Of course I will hear, but I like doing that... OK if that's how you want to cost your time.
73,
Carl - W9PMZ
---------------------------------------
Then you write…..
-----------------------------------------
I knew this was coming.........
You really didn't listen to what I said. I gave you tinkerers holed up in your shacks an out. It's not about economics, it's about personal choices.
From my point of view kit building was a way to save money. I suspect for most it was never about under standing how the equipment really worked (as a side note one respondent cracked me up as to his abilities when he talked about melting a coil in a MFJ tuner, connecting the tuner to a hi Z antenna, didn't he read the manual?); it was about getting on the air and talking to people! At least in the early 70s that what is was for me. I suspect most learning went on because in kit building,
1. Couldn't figure out the on knob,
2. Couldn't solder,
3. Couldn't follow instructions,
It was only then that you learned how to troubleshoot electronics from a schematic. At this point how may people understood really what was going on in a mixer?
Sure, I built my share of Heathkits; but it wasn't until I finished engineering school that I really understood the design and engineering behind the equipment. And I am still learning today! But I get nothing out of soldering wires and installing them on an insulator to see how it works.
All of you antenna builders; are you an Edison or Tesla?
Right now my priorities are my family and work and radio is a distant priority.
---------------------------------------------------
HUH excuse me but …. One could speculate that your a little slow on the uptake of electronics. Most people who built kits read the explanation of how it worked in the kit book (heathkit) and had a great understanding of electronics. After all most of the oldies that were doctors and lawyers that got ham licenses could use a iron and voltmeter. Most engineers that I know said that they learned more from building a radio than from engineering school where they had to take such courses as sexual race relations, music appreciation, art for the masses and least we forget the ever popular basket weaving 101 in spanish or the alternate... cooking for nutrition (burned everything) got kicked out of that class because we tried to roast the other white meat... the Fetal Pig that was from bio Dissection.. another great college course that meant a lot to me in later life... seems that it was soaked in femaldihide... the oven/room was never the same again so I was told...
As usual both sides of the fence the way I read yours.
Must have taught you that in engineering school too… when you get caught with your hand in the cookie jar.
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RE: What Happened To The Half Wave Dipole?
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by N6AJR on August 15, 2008
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RE: the G5RV
the G5rv is a pretty good 20 meter antenna that will tune on several other bands.
I see a lot of the folks here swear by them.. bUt have you had any thing else up to compare it too.
I started wuith a random length wire dipole and a tuner here, then I put up a 5BTV which worked better, then I put up a MA5B and it worked even better ,
thyen I put up a wilson SY-2 ( 4 element tribander) and it worked even better
I then put up a steppir 3 element beam for 6-20 m. ( 4 ele on 6) and it works even better, and I have a gap voyager ( verticle halfwave) and it does well on the low bands.
I still have the 5btv up, along with the steppir and the gap ( the 5btv is for the "other " rsdio in the shack).
I have had up dipoles, fan dipoles, Aplha-delta slopers and more.
They all work some but some work much better than others. that said I still have 1000 feet of copperweld in a box somewhere , just for playing.
and for a real fun antenn get a MFJ 927 or a sgc 237 and a long piece of wire into the neighbors tree.
folks, try many different different antennas and then let us know what is "BEST"
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RE: What Happened To The Half Wave Dipole?
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by W4LGH on August 15, 2008
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W5ESE on August 15, 2008 said....
QUOTING ME:
> Also if the length of the 1/2wave dipole doesn't fit
> your lot.... Use ladder line as a folded dipole and
> you cut the length in 1/2!! So that 130' 1/2wave 80M
> dipole just became 65 feet total length! Not quite
> as good as stretching it out fully, but it will get
> the job done nicely. Just short the ends, and feed
> one side of it.
His comment:
"I don't think this is right. A folded dipole is still
a half wavelength long. The advantage is somewhat
wider bandwidth and an impedance of ~300 ohms. So
you can feed it with cheap 300 ohm line instead of
more expensive coax. But the length is the same as a standard half wave dipole. 73 Scott"
Scott...
Me thinks you need to go back thru antenna class if you think that! Or at least clarify what you are saying! A 80M 1/2wave dipole is 130' long, 65' on each end. If you fold the wire back, the length is still 65' of wire on each end, but the overall length is 1/2 the distance, so you still have 130' of wire up, but it only stretches out 65' end to end. If you use 450ohm ladder line, you just short the outer end, and you only feed one side of it at the feed point. The feed impedance is still around 72 ohms. However you do broaden your bandwidth.
73 de W4LGH - Alan
http://www.w4lgh.com
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What Happened.....? What Happened?? Playoffs?????
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by N0AH on August 15, 2008
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I think that this is a good subject because it relates to perception. I had a Gap Titan and was thrilled. Then I got a Cushcraft MA5V vertical and I heard and worked a significant number of moe stations then I did switching back to the Gap. The Gap was a bg mess in the backyard. So the moral of the story is to try a couple of antennas before posting about a dipole. Without adequate support and height, which few of us have, a dipole is a nice bird wire. A low band antenna for those of you with room-
And of note to the last article about amps.......I read on a recent internet posting from www.fca/worldradio/34WTR/fr that beginning in 2018, world wide amateur band power output levels will be resricted to 200W.
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RE: What Happened To The Half Wave Dipole?
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by QRZDXR2 on August 15, 2008
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I agree.
Antennas are like wives. Everyone has to have one if they want to socialize. Antennas are like wives... no husband in his right mind is going to say she isn't good.
But,
Like all males... they are always checking out what the other guy has and compairing theirs' to what they have.
Sometimes they get a devorce and trade the old for a different one. Sometimes they stick with what they've got just because it would be work to change. sometimes they have the old... antenna ... upgraded so it is better.
But, in all cases most defend what they settled on .. be it antenna or wife... and become content to use what they have.
saying ones wife/ antenna is better than someone elses is really difficult because you don't know what they are like/ so many possibilities and so little time as they say.
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What Happened To The Half Wave Dipole?
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by G0DOQ on August 16, 2008
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I use a g5rv which I think is about as good as a dipole on 80 and can be used on other bands. Its one I purchased with 450 ohm and a choke balun.On 15 metres a g5rv has gain over a dipole, its also quite good on 17 metres. The most important thing is not to have a long run of lossy coax. This is because reflected power is re-reflected and will be absorbed in the coax instead of going back to the antenna I can tune it anywhere with an mfj 949 but it took me a while to get the hang of it, the tuner on my 870 also tunes it. I also have a half size which is better for 10 metres, and 20 sometimes
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RE: What Happened To The Half Wave Dipole?
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by KQ6XA on August 16, 2008
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"All antennas are dipoles."
You can quote me on that.
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What Happened To The Half Wave Dipole?
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by NM2K on August 16, 2008
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Many, many folks do not have the room for a half wave dipole on the low bands.
Lots of hams actually do use half wave dipoles on the higher bands.
The modern commercial groundplane less vertical has a much smaller footprint and can easily be mounted on a roof tripod without the need for radials or a counterpoise. Usually, the tuner that comes with most rigs can handle the tuning tasks required with ease.
Feeding the resonant dipole with 50 ohm coax will provide a minimum SWR of 1.5:1. If the ends of the dipole are drooped and adjusted properly, a suitable match can be found. However, all this antenna can do is operate on the primary frequency and a harmonic. The vertical described previously can often cover all of the amateur bands from 40 meters on up to 30 MHz.
If the dipole is fed with twinlead, it can be used as a multiband antenna and it works quite well. This is my favorite antenna these days, now that I have a large enough yard to accept its 102' overall length. My last home in NJ had a small, center of town, lot. I was limited to running verticals or shortened dipoles at that location. My present antenna works fine on bands up to 6 meters and down to 160 meters.
Ed, NM2K
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RE: What Happened To The Half Wave Dipole?
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by NI0C on August 16, 2008
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I agree with Carl, W9PMZ, that building circuits does not teach much about circuit theory.
I've taught college level electricity and electronics for over 25 years. I've also assembled Elecraft KX1, K2 and K3 radios from kits.
The kit building helped me practice parts identification as well as soldering and mechanical assembly skills. When it came time to wind toroid transformers, I've had to use the right hand rule to correctly identify the polarity of the leads. That's about it. Everything I ever learned about theory associated with resonant circuits, analog and digital filtering, mixers, AGC, A/D conversion, etc., was learned from textbooks, solving problems, and laboratory measurement.
Likewise, one does not learn Maxwell's equations by cutting wire for a dipole antenna or soldering a PL-259.
73,
Chuck NI0C
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RE: What Happened To The Half Wave Dipole?
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by W4LGH on August 16, 2008
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What happened to the 1/2wave dipole? Did someone lose one somewhere?
Antennas are like wives? Hogwash! I've had 3 wives and over a 100 antennas, none of them were even CLOSE! And none of the 3 wives have ever liked any of my antennas.
My present wife doesn't like heights, and all of my antenna LOVE heights.
All antenna are dipoles, Yes, because of their electrical dipole movement of current.
We have, Physical dipoles, Point dipoles, Approximate dipoles, Molecular dipoles & Electrical dipoles, now someone has lost a 1/2wave dipole?
Hmmmm, maybe it wasn't lost, maybe someone stole it?
73 de W4LGH - Alan
http://www.w4lgh.com
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RE: What Happened To The Half Wave Dipole?
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by NK5G on August 16, 2008
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I agree. The halfwave dipole is the most cost effective and efficient antenna that you can have. You don't need a beam and a tower to be a big gun DX station. (just look at what is commonly used on dxpeditions!)
Save your money and let physics do the work.
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What Happened To The Half Wave Dipole?
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by AD5FG on August 16, 2008
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My answers:
Apartments, small lots, and homeowner associations :(
Marketing, marketing, marketing. Look at the ads in the magazines.
I concur that wire rules, either dipoles or anything fed with balanced lines When had a nice tree available, I was partial to TV-twinlead since I never ran high power and my setup was always semi-temporary.
Now I live in an apartment in the Texas panhandle, there aren't many trees, so I am using hamstick-type things.
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RE: What Happened To The Half Wave Dipole?
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by AF4O on August 16, 2008
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Building dipoles and kits are what you make of it, like allot of things in life. If you choose to learn from kit building and dipole making, then there is a wealth of information to be had.
If you are the type to read a text book and retain that information from that point on, i envy you. As for me, my interest/learning curve is peaked when i have my hands in it and learn from the project at the same time.
One can build a kit, try and understand how each stage works (your choice), have a rig to be proud of that you built yourself, and come out more knowledgeable.
Then this for me has led to building electronic projects from scratch, repairing, and/or modifying. This takes the learning to another level. Be it test equipment, rigs, gadgets, etc. Been doing this on and off for decades (Ham for 30+ years, i'm 48).
I also agree with the statement that family and work is important. But having ones own time is important also. The balance is key.
I take this attitude with me at work also. If i am not learning constantly then i feel stagnant. Good thing i have about 10 hats at work.
Nice shiny rigs from out of the box are nice, i have quite a few, but nothing does it for me like melting solder (and i mean from that learning how a circuit works, building it, and using that gear).
Same with computers. Built them (no not from scratch, yet...), modified them, fixed them, read the books on how they work, currently using Linux (a whole new realm of learning!).
But thats just me. If simply taking a rig out of the box and hooking it to a store bought antenna does it for you, then more power to you. For me that would last a week and i would be burnt out.
Oh, i have 3 inverted vee dipoles and one windom. All coax fed but the ladder line sounds interesting. Ive never done that, yet.... Opps, got to go look up the theory on that.....
Oh, the comment about all those "low class old guys"; Sometimes when you get to know those old guys, you find most of them to be wealthy in knowledge and finances. They know how to retain both thus making some think they have neither.
Once you befriend them though, you find out the truth :-)
73
Chuck
AF4O
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RE: What Happened To The Half Wave Dipole?
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by W4LGH on August 16, 2008
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Seriously..I have said that the 1/2wave dipole was the best all round working antenna for years. Then everyone wants to throw that in my face. No tuner needed, and you can usually work the entire band, if you cut it in the middle. All of my antennas are 1/2wave dipoles, and I use a remote switch box to pick my frequency.
I have just finished building, one of my 4 end-fed 1/2wave verticals. Experimenting with it now, and getting really good results. It is 10' off the ground and extends up 33'. Seeing a 1 to 2 "S" unit higher signal level from DX signals. When finished, I will have 4 of them up, and be able to steer them electronically, thru a switching co-phase hookup.
73 de W4LGH - Alan
http://www.w4lgh.com
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RE: What Happened To The Half Wave Dipole?
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by KL7IPV on August 16, 2008
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Great article. I remember making my first antenna in 1966. I used telephone drop wire split in two and then hung at 50 feet with a telephone pole support. The ends formed a Vee with each leg being made for 80 meters. I also learned about coax and their coefficients and matched the coax to the antenna. Now I live in a CC&R HOA and use an InvVee under the eaves for 40 meters and an attic Slinky that spans 66 feet across my attic. I can use that for almost everything with a tuner. I would love to be able to get a tower again but until I do, the dipole is my favorite. But I also make my own vertical antennas for use in mobile and portable stations ( www.antenna-to-go.com ) that work well in other locations.
Frank
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What Happened To The Half Wave Dipole?
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by KC8HQX on August 16, 2008
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I'd love to put up a dipole. Anyone care to buy me enough land for one? And help with a support system to elevate it at least 1/2 wavelength on 80 meters?
Cheap, Compact, high performance.... Pick any two.
Doug
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What Happened To The Half Wave Dipole?
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by KD6HUC on August 17, 2008
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I use a fan dipole on 10-20-40 on roof of my "antenna restricted" apartment building. Due to wire actually sitting on top of asphalt shingles I had to do a lot of chopping to get them to resonate with a low SWR at the rig, but they are invisible and I get to operate without a tuner on those bands. Not a yagi, but much,much cheaper(junk box wire and twenty dollar coax) and invisible to the landlord. been a ham 16 years now and i keep coming back to the dipole. If you've never tried a dipole you are crazy!
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What Happened To The Half Wave Dipole?
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by OK1RR on August 17, 2008
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"A half wave dipole does not require a balun to work efficiently."
With highest respect to the author, this is not true. A real world dipole REQUIRES a balun, the common mode currents are a real problem! The 1/2 wave dipole is a good antenna but the dipole + the radiating feeder is a very bad wire garbage with unpredictable results. Let radiate your antenna, not the feeder!
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RE: What Happened To The Half Wave Dipole?
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by W0DLR on August 17, 2008
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A very good article.
I would only take exception with one point the writer made: "A half wave dipole can be built from scratch by the average HAM in half an hour or less."
I doubt that statement. Most can't solder a PL259 on a piece of coax.
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RE: What Happened To The Half Wave Dipole?
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by K2WH on August 17, 2008
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Nothing ever happened to the 1/2 wave dipole as far as I know. I have never used any HF antenna except a dipole even for 160 meters.
WAS, WAC, DXCC on multiple bands including 48 states on 160. Simple dipoles rock.
The G5RV craze is just alot of misinformation to new inexperienced hams and marketing ploys.
K2WH
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RE: What Happened To The Half Wave Dipole?
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by W4LGH on August 17, 2008
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OK1RR on August 17, 2008 said...
"A half wave dipole does not require a balun to work efficiently....
With highest respect to the author, this is not true. A real world dipole REQUIRES a balun, the common mode currents are a real problem! The 1/2 wave dipole is a good antenna but the dipole + the radiating feeder is a very bad wire garbage with unpredictable results. Let radiate your antenna, not the feeder!"
This statement is TRUE, but not really what was said. As with every post people read into whats really being said, and NOT really paying attention to what is really trying to be conveyed.
You do NOT have to USE a Balun to make a 1/2wave dipole. It is COMPLETELY un-necessary to the operation. However, adding a balun can in some cases correct some un-seen problems, such as common mode currents. However if the antenna is resonate on the desired frequency, and is equally balanced on both sides, there may not be any common mode currents. It has never been proven that adding a balun will improve overall antenna performance of a 1/2wave dipole. However I prefer to use a balun for several reasons, it can help keep problems to a minimum, it provides a way to connect the feed point of the antenna, and provides a way of supporting the center of the antenna. It is NOT necessary to make the antenna work, and work well. It's a shortcut.
Same with an antenna tuner in your shack, if your antenna is made correctly, it is NOT necessary, and it will NOT correct your antenna, it will allow you to use it, but at what cost in efficiency, RF problems in your shack etc. If you do not have room to put up full sized 1/2wave dipoles, that does not make it a bad antenna. We have all had to use "less than perfect" antennas over our ham careers, and that too, does NOT make it a good antenna, but it allowed us to get on the air, so we accepted it. Anyone that knows anything about antennas will tell you that a G5RV is not really a good antenna, hell most people don't even make it right, but we've all talked to someone on the air who was using a G5RV and getting great results. Those results however could be improved with a better antenna. The 1/2wave dipole is the "Pseudo defacto" of a good antenna, and is used as a standard in which to measure TRUE Gain over other antenna designs.. 10dbD, as in 10 DB gain over a 1/2wave Dipole.
Now I can hardly wait to hear the arguments over what I have said, cause I KNOW someone will read something else into what I said....
73 de W4LGH - Alan
http://www.w4lgh.com
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What Happened To The Half Wave Dipole?
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by N2NEH on August 18, 2008
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1/2 wave dipoles work very well as stated. However, has anyone ever tried a resonant feedline dipole? It's really just a modified 1/2 wave dipole, easy to construct, end fed, and is quite portable.
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RE: What Happened To The Half Wave Dipole?
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by KR4OW on August 19, 2008
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Yes it does become relevant in that you loose performance and waste energy needlessly
(At the antenna Frequency)
If you have a 80m Dipole fed with 450 ohm Ladder line to a 50 ohm Rig you now have a need for a 9:1 balun to match the 50ohm coax to the 450 Ohm feed line and then there is the miss match of feeding a 72 ohm antenna with a 450 ohm feedline.
SWR well if you have a SWR on the transmission line of 10:1 then you will loose 67 watts.
Tuner well if Match your 10:1 swr with a tuner. How much reactance do you have to match it? Remember that reactance is energy wasted not transmitted.
Same antenna now has a feedpoint of approx 31 Ohms at
40m. etc.... The point is that it is not that cut and dry to make a antenna work. like you think. Yes the antenna will work but not as it could Just an FYI
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What Happened To The Half Wave Dipole?
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by KD0QV on August 19, 2008
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As a Novice back in 1976, I made my own 40-M Inverted-Vee Dipole. Using some leftover house wiring, (12 gauge
Romex). Did the math, left a bit extra, and cut the Romex for One half length, split the Romex apart, and left on the Isulation. Thus, I had two,(2),equal halfs.
I used the Ground copper wire for my station Ground. Using a 40 ft. steel mast against the house on ground, the Dipole was installed as an Inverted Vee. The ends of the Dipole were tied off with Insulators & Nylon string. I made the Center Feedpoint out of a Plumbing Tee. I used "cheap" Radio Shack RG-58 coax directly soldered to the Dipole. This Antenna worked the world on both 40-M & on 15-M, Stood up to all kinds of Wind, Ice, and Storms for over 20+ years. It never needed a tuner, and worked just fine either on SSB or on CW. Total cost, very cheap, total pleasure very great!
73 & GUD DX. de, KD0QV--Jim in Iowa
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What Happened To The Half Wave Dipole?
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by K4FRC on August 19, 2008
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They're alive and well on 40m and 80m in my backyard.
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What Happened To The Half Wave Dipole?
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by N2OBM on August 19, 2008
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Well..well..it would seem the US Army has been wrong all these years. All the folks that sell baluns would have you think that you MUST have one to feed your half-wave dipole. Anyone hear of the GRA-50 and the 'IL-4' feed point a.k.a. 'cobra head'? How about the famous 'Hy-Gain'/ Collins tape dipole? What balun?
Yes, a balun could provide equal currents and maybe a more predictable pattern.
But by all means....put up what you have and GET ON THE AIR.
73,
OBM
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What Happened To The Half Wave Dipole?
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by WX7K on August 20, 2008
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Just put up my first dipole. Been using a Butternut for the last 20 years with good results, or so I thought. Moved to a new QTH and was having trouble hearing a guy 12 miles away on a local net. Teh Dipole solved that problem. AB testing the dipole with the Butternut was a real eye opener. A number of times I could hear a QSO on the dipole and not hear it or barely hear it on the Butternut. Makes me wonder how much I have missed over the years. Next stop is a multi-band dipole.
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RE: What Happened To The Half Wave Dipole?
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by K2WH on August 20, 2008
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by WX7K on August 20, 2008
"Just put up my first dipole. Been using a Butternut for the last 20 years with good results, or so I thought. Moved to a new QTH and was having trouble hearing a guy 12 miles away on a local net. Teh Dipole solved that problem. AB testing the dipole with the Butternut was a real eye opener. A number of times I could hear a QSO on the dipole and not hear it or barely hear it on the Butternut. Makes me wonder how much I have missed over the years. Next stop is a multi-band dipole."
Simple reason for that and it was NOT any antennas fault. A vertical is good for DX or long distance comms and due to the angle of radiation, most of it goes over the head of close in stations.
I dipole on the other hand, is usually (Most hams) too low for a low angle of radiation. Therefore, most of the signal goes straight up and then straight down for a strong local signal.
Both antennas work well and one was not working better than the other assuming they were both installed and fed correctly.
On HF, a low dipole and a good vertical are a must to work everything.
K2WH
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RE: Dipoles? I don't need...
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by AE1X on August 20, 2008
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K0RS,
Buddy,
Your problem is that of many of us today. We're only interested in working the almight DX counters and we forget that there are plenty of other contacts to be had, but we're to afraid to miss that new DX counter.
I've used dipoles and simple wire antennas. I operated in wee hours of the morning on 75m with 180' of wire and tuner and worked all over the US with 100w output.
On 40m, I had a resonant dipole at about 25' with a W2AU balun at the feed point, BTW I still have it. I've worked all over the place with it. My last antenna was a G5RV Jr at 25' feet and a Ten-Tec 270 tuner. That system is still up at my old QTH and had a blast with it. My favorite contact of all time with that system was on 30m. I was running 140mW and worked W4QBE in GA for MA. That's 821 miles. You figure it.
Now, what you say about achieving low take off angles, is entirely true and you are correct when it comes to DX, but that's not everything there is to amateur radio, but if we follow your logic it is. For me it's all about having fun. I miss having the Novices around with limited tickets. They would provide more opportunities for me to work stations with my 400mW 40m and 260mW 30m QRP transceivers.
Now, what the author of this article is saying is what we are really all about. We are suppose to be able to get on the air fast in the event of a disaster. I can tell you that throwing up a dipole can save your bacon. We had a problem getting on LoVHF in my town and I built a dipole from some wire I had around the EOC and was back on the air. Try that with all those fancy 800Mhz radios that the FCC is pushing for Government services.
BTW, those dipoles that are not up 1/2 wavelength are really NVIS antennas and they will work plenty of stations with little or no directivity.
The author of this article is right on about making contacts and with how little it will cost one and in a pinch, it could save someone's life. We need to reconsider a lot of our present day thinking to perserve out spectrum so you can chase you almight DX.
Ken - AE1X
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RE: What Happened To The Half Wave Dipole?
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by AE1X on August 20, 2008
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Crystal,
Come now. You should know better. The author was stating that the antenna has low noise pick up. The signals will be loud, but not as loud as would be the case with a gain type antenna.
What we all want is an antenna that will permit us to work the stations we wish to work. This means different things to different people.
Ken - AE1X
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RE: What Happened To The Half Wave Dipole?
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by W4LGH on August 21, 2008
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The real truth is, when it comes to HF antennas, there is NO "one size fits all!" There ARE those who will argue this until they are BLUE in the face. Some say, 130' of wire, fed in the center with 450ohm ladder line and tunes with a tuner in the shack, is as good as it gets. When in reality, this design has more flaws than Carter has little liver pills. an HF antenna can NOT be measured by "How many and how far away Contacts you make on it", that is purely dependent on atmospheric conditions, and truly has little to do with your antenna. When conditions are good, very small amounts of rf radiated will result is great contacts. When conditions are bad, they are still good, just NOT as good as they were. Increased amount of rf radiated will result is contacts still being made. Antenna design, correctness, amounts of rf generated, make very little difference, if any, making a contact 12K miles away on a 3 hop skip. If you truly want to test the effectiveness of your HF antenna, find a buddy 30-40 miles away. Some call this ground wave, but I like to refer to it as "Point to Point" communications. Here you will see a GREAT difference with different antenna designs, and how well he can hear you. You will also see big differences in using 50watts, 100watts & a 1000+ watts. This is where you can truly see how well you antenna really transfers the energy you put into it. Overall, the 1/2wave, center fed dipole, a 1/2wave about ground, is very effective, and will show you that you radiating more energy. More energy leaving you antenna, the DX contacts will get better too, just not as noticeable, but might make a difference in making or not making that 1 contact you've dreamed of.
For transmitting the 1/2wave is pretty good, now receiving, thats another completely different story, but the 1/2wave dipole works pretty good there too.
73 de W4LGH - Alan
http://www.w4lgh.com
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What Happened To The Half Wave Dipole?
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by KE5ICG on August 22, 2008
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Good Article -- glad to see it.
My answer: not a thing. I have 2 at my house -- one on 6m(51mhz) and one on 10m (28.4mhz). Both work just fine for me, but I also have other antennas (fixed and mobile) -- just got done with a "welding rod" beam for 2m.
Really, the dipole is just one of those basic things in radio everybody should try if they can. I got a lot of satisfaction out of putting mine together and hanging them -- but the best thing is making contacts with them.
73 and have fun -- Ray KE5ICG
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RE: What Happened To The Half Wave Dipole?
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by W4LGH on August 23, 2008
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Your welding rod beam is also a dipole. A dipole with directors and reflectors... but still a dipole.
73 de W4LGH - Alan
http://www.w4lgh.com
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RE: Dipoles? I don't need...
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by KI9A on August 24, 2008
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k0rs, do you have another $100 hytower?? That is a find, not something most can find. Also, agreed it will outperform a dipole out past 800 miles or so, but, for most domestic ( unless you are going coast-coast), the dipole will most likley hold it's own, and surpass the vertical. plus, you don't need a couple yards of concrete at what, $125/yard, plus you didn't mention having to dig the hole for it. Then pour it.
DX--I'll take the Hytower on 40/80, but, stateside from here in W9, I'll take the dipole. Nice to have both.
73-Chuck KI9A
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What Happened To The Half Wave Dipole?
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by KA2DDX on August 24, 2008
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I've been using dipoles for years - two years ago I bought a vertical to be the backup antenna to my dipole, in case the wind blew the dipole feed line all over the place (again). Earned dxcc with my dipole. Finally figured out how to better secure the feed line also. Best of both worlds. Dipoles are inexpensive and work, period.
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What Happened To The Half Wave Dipole?
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by K2LCK on August 26, 2008
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good article , correct. if the users of other than a dipole were aware of the limitations of other antennas.... All antennas that are not dipoles exist as some kinda compromise, usually freq response or size. (a beam is a dipole with reflectors and directors added)..
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What Happened To The Half Wave Dipole?
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by N7XFT on August 26, 2008
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This is a good article. You don't need to spend a lot of money to really enjoy this hobby. Dipole antennas are one good example.
I don't have the ability to put up a nicely tuned dipole for the four bands I operate most so, I use an OCF inverted vee that does very well on all bands except 30m with my tuner. For 30m, I have a nicely tuned dipole that works great. :) The OCF inverted vee is a 'clone' of the one that Buckmasters sells for a lot of $$$. It is 45' on the short side, 90' on the long side and uses a 6:1 balun at the feed point. Even without the tuner it works well on all bands but is a little bit narrow on 15m and 80m.
That's my story and I'm stickin' to it! :)
73, Paul - K7IN
Cold Springs, NV.
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What Happened To The Half Wave Dipole?
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by W8LV on August 30, 2008
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And..lets not forget the half wave dipole fed with ladder line (OK...with a balun)...and the low take-off angle king of them all, the Half-Square! Whilst I use a vertical mostly here at home, and I had a nice vertical portable, the diploe, in any configuration is still the most "Portable" and versatile. You can transport it anywhere, whether as a carry-on for your next plane trip in post 9-11 land, or just thrown into the back of a vehicle. No specialized elements to bend or break, no missing screws or clamps to contend with, and with a wind loading factor of...oh...about "zero", it will stand up to mother nature the way an expensive commercial unit just can't. A well done forum message, methinks.
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What Happened To The Half Wave Dipole?
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by WA0DTH on September 2, 2008
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I think the half wave dipole in many cases is serving as a balanced radiator for other bands.
Be it a G5RV or ladder line fed.
I know at my station I have gone to 460 ohm ladder line and a balanced line tuner.
I did this for better performance and the ability to use the dipole not only on its resonant frequency and or harmonics, but to tune the system to none resonant frequencies.
Nothing wrong with the coaxial fed dipole or inverted vee. I used one for many years. And it is one of best of the simple wire antennas.
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