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 monoband vertical 
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Post monoband vertical
quick (and probably simple to answer) question: does a half-wave monoband vertical antenna require counterpoises?

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Thu Apr 28, 2011 5:55 pm
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 monoband vertical 
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Post Re: monoband vertical
It depends where it is fed.

If it's centre-fed, no - it's a complete antenna in its own right. If it's end fed, something else needs to be the other half of the antenna - if you don't provide radials, then it will be your coax braid.

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Steve G3TXQ


Thu Apr 28, 2011 6:06 pm
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 monoband vertical 
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Post Re: monoband vertical
that's kind of what i thought. I saw some some monoband mini-dipoles on the Sandpiper website. I know they will never be ideal but nothing will in my situation. Would, say, a 40 meter minipole tune down to 20 well enough or should it be used strictly on the band for which it was intended?

Thanks Steve

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Thu Apr 28, 2011 6:12 pm
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 monoband vertical 
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Post Re: monoband vertical
It depends what you mean by "tune down to 20".

If the 40m dipole is adjustable and you can get it to resonate on 20m, that's fine; but if you mean leave the dipole at its 40m setting and try to match it with a tuner back at the shack, you'll get very high losses in the coax feedline.

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Thu Apr 28, 2011 6:49 pm
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 monoband vertical 
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Post Re: monoband vertical
this is what i mean:

http://www.sandpiperaerials.co.uk/index ... th=3_20_42

So single band then.

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Thu Apr 28, 2011 6:56 pm
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 monoband vertical 
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Post Re: monoband vertical
Looks like it!

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Steve G3TXQ


Thu Apr 28, 2011 7:02 pm
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 monoband vertical 
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Post Re: monoband vertical
one last question...i promise. 60 meters or 20 meters? would i do ok on 80? i'm not expecting miracles, just the odd ragchew.

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Thu Apr 28, 2011 7:15 pm
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 monoband vertical 
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Post Re: monoband vertical
I think I can answer that.
the closer the length of the mini-dipole is to the wavelength of the band in use, the more efficient it would be.

so 20m would be more efficient than 40/80m, simply because there is less loading involved.

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Sat Apr 30, 2011 9:48 am
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 monoband vertical 
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Post Re: monoband vertical
ah. sorry my finger slipped. that should have read 80 Meters? I've decided on 20 anyway. no room for loads of antennas anyway. I would still like to hear your thoughts on 80 meters.

Thanks for your assistance.

73

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Sat Apr 30, 2011 10:31 am
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 monoband vertical 
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Post Re: monoband vertical
i meant the 80 meter band. if i got a mini-dipole for 80 meters, how would i do?

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Sat Apr 30, 2011 11:05 am
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 monoband vertical 
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Post Re: monoband vertical
http://www.miracleantenna.com/MMD.htm

you could try one of these mixed mode dipoles, i'm thinking of making one myself..


billy

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Sat Apr 30, 2011 11:22 am
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 monoband vertical 
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Post Re: monoband vertical
m0jha wrote:
http://www.miracleantenna.com/MMD.htm

you could try one of these mixed mode dipoles, i'm thinking of making one myself..


billy


Sounds good. Sadly I don't have anywhere to put a proper dipole for the time being....

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Sat Apr 30, 2011 11:33 am
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 monoband vertical 
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Post Re: monoband vertical
drop it off the balcony , its not like a normal 2 leg dipole , its phsically more like an end fed . its one straight run of coax with a choke then the feedline..

billy

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Sat Apr 30, 2011 11:36 am
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 monoband vertical 
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Post Re: monoband vertical
m0jha wrote:
http://www.miracleantenna.com/MMD.htm

you could try one of these mixed mode dipoles, i'm thinking of making one myself..


billy


It looks like a bazooka with a RF choke, Billy you could knock one of those in the space between the characters than form A, CMD my arris :D

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Sat Apr 30, 2011 11:50 am
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 monoband vertical 
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Post Re: monoband vertical
bazookas are fed in the center arnt they ? The MMD is different

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Sat Apr 30, 2011 12:12 pm
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