vertical antennas

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K1JJ:
Sure, anything will "work" and you will get many opinions.  Some of the guys run Windoms with excellent results.

But it's hard to beat the proven design and performance of a balanced dipole as I described. 

Receiving the other guy is half the battle as well as being heard when QRM and conditions get rough. Do all you can to get that antenna up as straight, flat and balanced.  A simple dipole is hard to beat.

Well, back outside for some more work... I'm black out.

T

KZ5A:
The usefulness of Verticals is highly dependent on local ground conductivity.   At my present QTH in Tyler, TX they work great because of the very high local ground conductivity,  At my "other" QTH in the mountains of New Mexico they are a waste of time due to the poor ground conductivity.

Dipoles are OK, but require 2 or 3 supports and if they are high enough to work DX off of the sides, they are dead off of the ends.  Not particularly a good plan if you only have one antenna.

Personally I prefer inverted V's for low band work.  They only require one support, are fairly forgiving of installation irregularities (like not having the two sections in line) and are generally omni-directional.   Here I'm blessed with several 60 -70 foot pine trees and have a 75M Double-Bazooka inverted V with the center up about 50 ft in a pine.  It "used to be" abt 60 feet up in the center but the support rope broke and the center dropped to about 50 ft and but stayed up so I've just left well enough alone.   

Not having tall trees to work with, the commonly available military surplus 4 foot fiberglass mast sections can be used as an economical center support for 40 or 50 ft before they get too wobbly.  If you pull the legs of the V out with around 120 degrees of separation you can get away with one guy.

I usually join or listen to the "Texhoma Traders Net" on 3890 on Saturday mornings and find that I generally can copy a greater percentage of the check-ins than most anyone else with my inverted V. 

Also, obsessing on making a dipole "flat"  is pointless and maybe even counter-productive.  Dipoles are installed in all sorts of configurations, V's, slopers, flat tops, bent on the ends.... what ever fits the available supports will work reasonably well.   The theory that they have to be flat and straight to work is a bunch of hogwash.   The higher it is in the center, the better it will work for DX.

Another popular approach to 160/80/40 is a full wave loop for the lowest band. feed with balanced line.   Whatever shape the available supports allow will work, but the closer to round the better.  I haven't tried one of these but a lot of hams swear by them.  Most people I've heard using one of these have them at 30 to 50 feet.

Copper house wire is heavy,expensive, and prone to stretching.  Copperweld is a better, cheaper, wire for antenna use. 
 
See http://www.thewireman.com/antennap.html 

73 Jack KZ5A

K1JJ:
Quote

Also, obsessing on making a dipole "flat"  is pointless and maybe even counter-productive.  Dipoles are installed in all sorts of configurations, V's, slopers, flat tops, bent on the ends.... what ever fits the available supports will work reasonably well.   The theory that they have to be flat and straight to work is a bunch of hogwash.   The higher it is in the center, the better it will work for DX.


Here we go again.

ANYTHING  will "work".  But compared to what?   The standard is a flat, straight dipole. Any departure from this is a compromise. Model it and see.

As we lower the legs of an inv V, they start to cancel radiation. Bring them down below 90 degrees apex angle and your input impedance starts to drop - continue to lower them until we get no radiation at all as the legs  become parallel as a feedline.  Also, the average height goes down as the legs are dropped and the take-off angle goes up.  Add a reflector or director and the front-to-back ratio (and gain) gets poorer with inverted V elements compared to flat  dipoles.

Why do they make Yagis with flat elements? They could use inverted V’s if they desired. But flat dipole elements are the best performers over ground, that’s why.

BTW, slopers are possibly the worst use of a dipole for DX work. They radiate off the sides better than in the direction of the slope. Surprise, surprise… that’s how dipoles are supposed to radiate – broadside.  Slopers were a big thing in the 80’s on 75M before the DXers wised up and went back to high dipoles or Yagis.

OK, I realize we are splitting hairs here and the guy looking for advice will probably end up with some wire hung in the trees somehow, but that’s no reason not to teach him the best method first. Maybe he had the perfect supports to put up a flat dipole, maybe not.  If we have to use inv v, or inverted U’s or whatever to get a dipole in the air, so be it.  But to tell the guy that striving to make a dipole flat is pointless and counter-productive (and hogwash) is ridiculous.

Tom, K1JJ

W2DU:
Amen to your rebuttal, Tom.

Walt

K5UJ:
<<<Another popular approach to 160/80/40 is a full wave loop for the lowest band. feed with balanced line.   Whatever shape the available supports allow will work, but the closer to round the better.  I haven't tried one of these but a lot of hams swear by them.  Most people I've heard using one of these have them at 30 to 50 feet.>>

Then you should try one.  I have.  Loops suck unless you can get them way high, higher than most hams are able to do.   If you have four or more really tall trees, as in over 100 feet, then go for it.  Lower down on 75 there is too much wavelength exposure and ground loss through coupling to earth and on 160?  Fugeddabodit, unless you can get the loop up around 150-200 feet on that band.  

Somewhere on one of his pages, Cebik said small and high (high dipole) beats big and low (loop at 30 or 40 feet) any day of the week.   Don't make the mistake of thinking that because of its size, a loop is a great performer.  Height is everything.  Height directly = dBs and is really the only legal way to get a lot of them but, height is expensive.   Therefore, if you can only afford one or two 50 foot supports, you are far better off going with a dipole than several short poles holding a loop.  

On a dipole it is okay to let the ends dangle down if you have to.  But, there is a big difference between the ends hanging and an inverted V.  I have a 130 foot dipole on my 100 x 50 foot lot with 20' on each end hanging down (dipole is at 50').   I  don't have the big signal I'd like to have (few of us do) but I can usually make contacts and it is much better than the 1 w. loop I had on 75 at 25 to 30 feet before.   You will be amazed at what a simple high dipole can do.   Most of the big AM signals on 75 are from guys who have nothing more than dipoles up around 100 feet or more.   If you didn't know you'd swear they were running 2 kw broadcast rigs.  But they are often running no more than 300 w., sometimes much less.   Antenna is everything.

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