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Base My homemade dipole, success, but,,,,,,,,,

Tuning the antenna at 10 feet off the ground then raising it WILL cause a change in SWR. Ten feet is just too close for 11m. You may even see a difference at 20 feet. Also sticking it thru the top of the tower is BAD.
 
Ok worked on this all day.

Scratched putting it on my tower. Was just too dangerous up there trying to make this work. Ended up with it being horizontal and on a 20 foot pole, the top part of the pole being 2 feet of pvc.

After MANY tries, up and down, trimming and soldering, swearing and cussing, laughing and crying, I ended up with 1.6 on 1 and 1.5 on 40. A solid 1.5 in the middle of the band. I just couldn’t get it any better.

Not as low as I hoped, but not as high as they were.

I have no regrets. This was a great learning experience
 
I buy a piece of uni strut at home depot or lowes, you will find it in the electrical section.
It has holes in it and U clamps fit perfect. Cut it so about 3 feet sticks out the side of the tower
I U clamp it to my tower, on the end of the uni strut I U clamp a pulley, use Dacron rope and pull my wire antennas up and down from the ground. Climb the tower once and be done with it.

I use plain ole 1/2 inch pvc for insulators on the end of the legs and more Dacron rope to tie the legs to what ever is handy, ( I would like to tie it to some of the wifes cats that would be a hell of a hoot until she came out to see what all the noise is).

Building wire antennas is fun and there are many different types to experiment with and build. As for the sweet sixteen. Inverted V will drop right down to a 1: VSWR.
http://www.hamuniverse.com/antennas.html
I also use RG6 quad coax for my dipoles. 75 ohm to 73 ohm dipole gives me a decent VSWR as long as I can trim the rg6 in 1/2 wl of the frequency I am using on the dipole.
RG6Quad is cheap, like $89 a 500 foot spool,
I use it on my 75 meter dipole, works with no issues and the price is right as Bob Barker used to say
 
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Actually that's pretty much correct! A horizontal dipole has roughly an Impedance of 70 to 75 Ohms(73+/-)…
1.5:1 is DEAD on!
Trying to lower the VSWR will actually push the antenna out of resonance.
Mounted on the pole should give you the ability to turn it. Even at 20 ft. it will be "Slightly" directional off the broadside, with a null on the ends.
Have fun
All the Best
Gary
 
Hey Gary, do you think 20 feet will be sufficient.? I’m wanting this to run on a separate radio for skip purposes. I already have a Maco V58 that’s 60 feet up . I could probably get this higher if I just keep working at it over the next few weeks unless and it’s just not really worth it.
 
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More height is always better, but try it for awhile and see.
I had a homebrew 6m dipole made out of scrap Alm tubing at 45 ft. and was steerable...worked pretty damn well...worked all over N. America and Carribean with it just using a 100w radio...got lucky once and even made a couple contacts in Africa, under REALLY good conditions.

PS: That was from Central Indiana(y):ROFLMAO:
 
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Kevin: One more thing. You'll find out real fast how well you did on the construction of the center insulator and terminating the coax etc.
When you start stroking that antenna with a big amp!:eek:
They can be made to handle 2KW, but takes some good construction practices to do so.:LOL::D
All the Best
Gary
 
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I guess I just don’t know where to set my expectations. I don’t mean this in a cynical way. I’ve never had anything except verticals. When skip rolls in, I pick it up on my maco and take advantage of it. I decided I’d like something dedicated towards skip. I just don’t know if this dipole will do any better than my Maco. My plan was to get it right under the maco, about 40 feet up or so. I guess I’ll have to wait and see what performs better when it rolls in again.

I have done a lot of reading, and got interested in making antennas. My first one ended in doom. Hindsight, I think I was just way too short on it and actually took it off frequency without realizing it and gave up on it.
 
Morning Trucker Kevin. Set up looks basically like the one BJ posted in the tower picture in a previous post. The stand off with the 40/80 meter dipoles on it.

If you going get serious about wires, investing in a few 1:1 current baluns will help tremendously, in building and installing.

I am gong post a few links to hopefully give some information and insight to take off angles and parts used to adapt the 75 ohm coax to so 239 or pl 259.

http://www.dx-antennas.com/Height versus take off angle.htm
https://www.qsl.net/w4sat/antenna.htm
http://www.westmountainradio.com/antenna_calculator.php?frequency=576
http://www.hamuniverse.com/wb4yjtdipolepatterns.html

Last link shows 1/2 wl agl radiation pattern, it will surprise you just what you can do on DX with your dipole 18 feet high

This is where I purchase my adapters I have never had one fail, and I run ( cough cough ) full legal limit power out.

https://www.ebay.com/itm/SMA-Female...=333018781826d89e93aeaeb448ea872390be8e86d41c
 
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Thanks for that!

I had really considered using a Balun, and had even found the parts here to make one. But from what I read during my research,,,,, most were saying a Balun wasn’t needed? I wonder if that would have helped me with some of my troubles.
 
Hello All: Yeah I like the BJ radionut way of being able to hoist up and down a wire antenna using a pulley, I have one on my tower and its great to run up a dipole or what ever wire antenna I want.

The dipole 1/2 wave antenna should have a 1 to 1 Current type Balun, in my simple minds opinion. I have installed quit a few dipole antennas using old TV RG59 and RG6 coaxes and what ever I had laying around. What I think happens is the length of coax shield may or may not radiate RF Energy causing some VSWR problems. Talking with the Engineer at Alpha Antennas, (who sell multi band dipole antennas) about the use of a Balun on dipole antennas, he said. "You can use a Balun if you want but not always necessary" I plane on testing this Balun, No Balun theory when it cools off some what here in the Mojave Desert.

The locals here in the desert all showed up on 20 meters and invited me to joint in or they were gonna bad mouth me. Charming. So I made a 1/2 wave length wire dipole for 20 meters, which came out to 16 1/2 feet for each leg, and made a 1 to 1 current Balun with a VSWR of about 1.2 to 1 not bad for the first time around. Used the formula 234 divided by Frequency in Mc and got 16.4 Ft for 14.250 Mc. The Balun (P/N FT-240-K) used two 2.4 inch cores epoxied together and used 2 each 10 turns of 14 gauge enamel wire, to make a Current type Balun. See:
http://www.amidoncorp.com/ab240-250-kit-k-mix-balun-kit/

Yeah the cores cost around 20 bucks each but they work and can take the high output power some of you use.

Please keep us updated on your progress. Great stuff here shared.

Jay in the Great Mojave Desert
 
Dipole is a balanced antenna, coax is unbalancd transmission line,,thus the BALUN balanced to unbalanced.

They do help reduce CMC on the coax and forces equal current to each leg of the dipole.

I have used the baluns, and have built some dipoles with out baluns. I cant tell the difference as neither one tears up my computer speakers.
In theory the balun is supposed to be part of the antenna system, in real world experience I guess you just have try it and see how it works
 

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