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 Can someone model a simple doublet for me please. 
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Post Can someone model a simple doublet for me please.
Sorry to ask, I know I should do it myself.

Simple doublet 31.1metres each leg, 15m 300ohm ladder line with a 4:1 balun to coax.

I want to see if it's going to tune on top band and 80m please.

Ta
Alan

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Tue Jan 09, 2018 9:08 am
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 Can someone model a simple doublet for me please. 
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Post Re: Can someone model a simple doublet for me please.
I can't do it at work, but any one who does is going to need to know how high.

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Tue Jan 09, 2018 9:44 am
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 Can someone model a simple doublet for me please. 
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Post Re: Can someone model a simple doublet for me please.
15m high.

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Tue Jan 09, 2018 9:46 am
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 Can someone model a simple doublet for me please. 
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Post Re: Can someone model a simple doublet for me please.
Basically will be fine on 80m and will work on top band (not very effiecient).

I presume you are using a Current Balun and not a Voltage Balun.

Regards

Keith G0TSH

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Tue Jan 09, 2018 12:10 pm
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 Can someone model a simple doublet for me please. 
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Post Re: Can someone model a simple doublet for me please.
I might be able to extend to a half wave on 160 now I've spoken to the station manager (should be good for 80 as well).
Yes a current balun as I need to keep the balance and the feedline clean.

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Tue Jan 09, 2018 12:55 pm
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 Can someone model a simple doublet for me please. 
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Post Re: Can someone model a simple doublet for me please.
If you require more tuning performance from a doublet based antenna then look at this: http://www.hamuniverse.com/cobraantenna.html
Ignore some of the measurements as it is basically a folded doublet and therefore you can make it fit your particular needs, this will aid your quest to get onto the top band, the antenna does not outperform that of a regular balanced doublet but it does allow you acquire a better match for the tunning network.

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Tue Jan 09, 2018 12:55 pm
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 Can someone model a simple doublet for me please. 
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Post Re: Can someone model a simple doublet for me please.
2E0JGR wrote:
If you require more tuning performance from a doublet based antenna then look at this: http://www.hamuniverse.com/cobraantenna.html
Ignore some of the measurements as it is basically a folded doublet and therefore you can make it fit your particular needs, this will aid your quest to get onto the top band, the antenna does not outperform that of a regular balanced doublet but it does allow you acquire a better match for the tunning network.


Cheers I've already looked at this, and fan dipoles. I only want a single wire (it's to do with the tree in the middle).

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Tue Jan 09, 2018 12:59 pm
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 Can someone model a simple doublet for me please. 
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Post Re: Can someone model a simple doublet for me please.
M0XAL wrote:
I might be able to extend to a half wave on 160 now I've spoken to the station manager (should be good for 80 as well).
Yes a current balun as I need to keep the balance and the feedline clean.


No. Leave it as it is. It falls nicely about half way between the problem frequencies. Avoid half waves and full waves unless you can run the twinline straight into the ATU with no coax.

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Tue Jan 09, 2018 1:03 pm
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 Can someone model a simple doublet for me please. 
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Post Re: Can someone model a simple doublet for me please.
M0XAL wrote:
2E0JGR wrote:
If you require more tuning performance from a doublet based antenna then look at this: http://www.hamuniverse.com/cobraantenna.html
Ignore some of the measurements as it is basically a folded doublet and therefore you can make it fit your particular needs, this will aid your quest to get onto the top band, the antenna does not outperform that of a regular balanced doublet but it does allow you acquire a better match for the tunning network.


Cheers I've already looked at this, and fan dipoles. I only want a single wire (it's to do with the tree in the middle).

It is not a fan dipole by any means it is a doublet element that is shortened and folded back onto itself, I showed it to G3TXQ and his answer was that it is just a folded doublet nothing too special apart from the wider tuning range offered. But if you can fit 80m in then go for that as that is the best option overall.

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Tue Jan 09, 2018 1:08 pm
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