Long Wire on HF ?

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SCPD

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I am looking at setting up a long wire antenna for HF on 20 meters and 10 meters. I have the following LDG IT-100 tuner and LDG RBA-4:1 balun. I am using a Icom IC-7000 radio.

Tuner: Products LDG Electronics

Balun: Products LDG Electronics


Also .. is there a best type of material for the wire ? (I am thinking of using stranded copper wire)
 
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zz0468

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That's probably not the best tuner for use with random wire (frequently mislabed 'long wire') antenna. From the link you just posted:

First, it matches up to 10:1 SWR (3:1 on 6 meters), so just about anything you can feed with coax is good to go.
So, with the balun you linked to, you would make a doublet - a dipole configuration fed with open wire line, with the balun transitioning to coax, and then to the tuner. That would probably work pretty well, but the LDG tuner might not be capable of tuning all frequency bands. They're supposed to work ok with something like a G5RV antenna.
 

LtDoc

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Will a random or long-wire antenna work with your LDG tuner? maybe, just depends on how long that wire is and what it's input impedance is. How about using that balun? It may or may not help things. It depends a lot on which particular band you happen to be on, and just how far off that antenna's input impedance would be on that band. One simple way to find out is to put it in-line and see if the tuner 'likes' it or not. If not, then take it out of line (fairly simple with a switch).
If you find that there's a band that the tuner and wire combination just won't work on, try adding or subtracting a few feet of wire to/from that antenna. There will be places it just won't go. So, change something till you find a 'sweet spot'.
- 'Doc
 

SCPD

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Well ideally we should be using something like an ICOM AH4 tuner (I think thats the model ?) but you just cannot go out and buy everything in sight.

I know of a local expert that I will see if he can assist us .. as well isn't that what experts are for ?

I will admit that I am NOT a builder or tinker'er type of person, so if I cannot buy it off the shelf it is not going to happen. I know .. and we call ourselves hams. *hehehe*

Thanks for the input .. it is all appreciated but I don't think that a decision will be made on what we will do for about another week.

But I am kinda warming up to the G5RV antenna .. but just have never used an antenna with that type of feed line / as compared to coax.

Thanks ..
 
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SCPD

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Beam antenna

I didn't see this mentioned, so I thought I'd bring it up.

A straight end fed wire that is more than a wavelength long acts like an beam off the end of the wire.
The longer it is, the more directional it becomes.
 
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N1BHH

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You will be better off building a dipole and feed it with twin lead or ladder line. If you build one to be fed with coax, all you need is 3 dipoles fed commonly and spread out as best you can. I never buy antennas, I build them and have more fun doing it. A G5RV is technically only good for 20 meters. I had one that I built and experimented with the lengths as I was only using it for 80, 40 and 20 and found 110 feet was ideal for my setup, which had the coax feed buried underground, no RF feedback anywhere.
 

AA1LL

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I also vote for making a balanced horizontal dipole as high as you can get it. At Home Depot, buy a roll of dog fence wire which is number 16 insulated stranded copper wire for the antenna. Use 300 ohm twin lead or even clear speaker wire with >#16 wire to feed it in the center and use the ugly balun (referenced above; no ferrite) inside the shack to interface the feedline to your unbalanced tuner. This way, the need for a good RF ground is minimized. If the antenna is 100 feet long it should work pretty well on 17-80 meters. As someone suggested, trim or add to the feedline if it won't tune. For the higher frequency bands, build a ground plane antenna up high. You can get really good antenna insulators at Tractor Supply or Blue Seal -- use their heavy duty electric fence corner insulators!!
 

SCPD

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Interestingly .. one of my friends told me today that he was receiving 10 meter FM repeaters from the eastern coast (I am in western Canada) on his Uniden BC246T scanner with a 2 meter 1/4 wave antenna attached.

So .. sounds like 10 m is really happening. I think I will pick up a 10 meter hamstick so I can see what I can listen to.
 

AA1LL

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yes 10 meters is FINALLY open pretty much daily, and now is a great time to start working on antennas for it. Sorry I misunderstood the original post about a long wire antenna for 10 meters. You can feed a multiple wavelength antenna a quarter wave from one end and get an input impedance close to 150 ohms. Your gain will be respectable, and in the direction of the wire, as someone else pointed out. Just for fun I did a NEC simulation of a 62.3 meters (204') long number 16 copper wire 10 meters (33') high over poor ground. (attached) You get about a 3:1 VSWR and 12dB gain at a really low takeoff angle. Not bad if you just want to communicate in 4 directions that are across from each other...
 

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