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 Pondering again 
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Post Pondering again
A little question if you please :

what I want to know is out of the below 2 antennas which would be better for 80M use

A 66ft end fed wire with a good quality 9:1 UNUN at the feedpoint with a 20M counterpoise OR (fed via 8M of RG mini 8 coax)

An off centre fed dipole 56 ft and 28ft with a good quality 4:1 Balun at the feedpoint ? Coax run would be only around 8M of RG mini 8.

If I had a balanced tuner I would probably stick a 84ft doublet up fed with 300 ohm feeder

The balun and UNUN manufactured by Gwhip, so not your cheap tat. Picked them up at a good price at the Hamfest so may as well put them to use.

I am just wanting something to get me up and running on 80M nothing serious as I prefer 40 and up. I know both are not ideal and will be lossy BUT just how lossy and crap would they be???

No room for a 132ft dipole, in fact 84ft is pushing it even in a inverted V configaration.

Thanks Ian M0IOD


Thu Mar 05, 2015 8:33 pm
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 Pondering again 
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Post Re: Pondering again
84ft is simply too short for 80m, especially when fed by coax.

Out of those two options the end-fed is the better bet, and at 66ft you shouldn't need an UnUn!

Steve G3TXQ


Thu Mar 05, 2015 10:01 pm
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 Pondering again 
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After trying lots of wire antennas that would fit in my small space, I have ended up with an end fed almost inverted L, and it's performance is way ahead of anythying else I have tried. It works on 80, and works well on 40 and above.

Fed with a 5:1 unun and ferrites on the coax about 20' from the feed point. The feed point is as far from the house as I could get it.

9:1 and 4:1 didn't allow the internal tuners to tune it on all bands, but that may well change with height and location.

It was also the easiest one to make :)

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Fri Mar 06, 2015 4:01 am
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 Pondering again 
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A 75ft long inverted L 25ft vertical and 50ft flat top was one of my contest winning antennas. It was limited to about 4000-5000 miles on 80m but I made plenty of contacts with it, contributed more than 50% of our clubs score in the RSGB 80m CC and Sprint contests and it was a cracking antenna on 40m.

Get yourself a SGC230 Steve and put it at the feedpoint. I think you might be pleasantly surprised how well it operates on the higher frequencies where it'll start to generate some lobes with some pretty nice gain.

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Fri Mar 06, 2015 1:52 pm
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 Pondering again 
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Post Re: Pondering again
G3TXQ wrote:
84ft is simply too short for 80m, especially when fed by coax.

Out of those two options the end-fed is the better bet, and at 66ft you shouldn't need an UnUn!

Steve G3TXQ



Cheers Steve. I suppose only plus as to feeding via an UNUN is that it will tune on other bands too. However losses will probably cancel that out.I will play about, the 84ft doublet when fed with the ladderline via the balanced tuner worked pretty well ,however as we know coax is another kettle of fish altogether :)


Sat Mar 07, 2015 5:08 pm
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 Pondering again 
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Sangoma wrote:
After trying lots of wire antennas that would fit in my small space, I have ended up with an end fed almost inverted L, and it's performance is way ahead of anythying else I have tried. It works on 80, and works well on 40 and above.

Fed with a 5:1 unun and ferrites on the coax about 20' from the feed point. The feed point is as far from the house as I could get it.

9:1 and 4:1 didn't allow the internal tuners to tune it on all bands, but that may well change with height and location.

It was also the easiest one to make :)


What is the physical length of the antenna ?

Cheers Ian


Sat Mar 07, 2015 5:10 pm
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 Pondering again 
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M0GVZ wrote:
A 75ft long inverted L 25ft vertical and 50ft flat top was one of my contest winning antennas. It was limited to about 4000-5000 miles on 80m but I made plenty of contacts with it, contributed more than 50% of our clubs score in the RSGB 80m CC and Sprint contests and it was a cracking antenna on 40m.

Get yourself a SGC230 Steve and put it at the feedpoint. I think you might be pleasantly surprised how well it operates on the higher frequencies where it'll start to generate some lobes with some pretty nice gain.


Conor

I tried a similar antenna with my CG 3000 ATU and it worked OK on 80/40 and even allowed me to make contacts on 160M, but on the higher bands it was not a patch on my vertical as it was physically too long. Shortening the antenna made a marked difference on bands 20M and up.

I am covered with my windom on 40 through to 6M with good results both local and DX.

I have, would you believe an Antron 99 !!!(cost me all of £10 :) with a modified top section which is now resonant somewhere around 18.15mhz. This is my vertical that I use on 17 through to 10 and it is on a par and sometimes better than the windom, depending on the orientation of the station worked to me.

I also often work DX on 20M with it although the windom is usually a fair but up on 20M although again the orientation of the station worked to me sometimes makes the vertical a better option.

The new antenna will be orientated in a different plane to the Windom.

I really should have clarified my question. I want something that will "work" on 80M (tune and allow me reasonable Inter G contacts) and will also work on as many other bands as possible.

The reason being it will be a fall back antenna on the other bands should any problem arise with the windom or vertical.My FT 817 will plug into it and allow me a second HF receiver while my 7600 is usefully employed.

Thus the idea of the 9:1 UNUN at the feedpoint,allowing a few more bands than just 80M.

If I go down that route it will be a quality investment, maybe a UNUN manufactured by Gwhip. I do not want any of the cheap and nasty affairs offered on ebay.

The Antron out performed the inverted L (on 20M up) which I had hooked up to my CG 3000 which may now become surplus as I have a small SGC 11 for portable use and can be used in case of dire antenna problems . Only rated at 60 watts PEP so power down if I ever have to press it into use at home. It works a treat with my 817 when out portable.

Anyway thanks all for your input, I will discount the 84ft dipole, I may just revert back to the good old W3EDP ,cheap and cheerful.


Sat Mar 07, 2015 5:29 pm
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