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 G0KSC Antenna Query 
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Post G0KSC Antenna Query
Hello,

I have sourced a 2nd hand Innovanntennas 8el LFA. I think its an old one, I have disassembled and cleaned it up and its just about ready to go up, its looking nearly new now.

Can anyone tell me if I need a choke balun on it at the feed point?

Additionally, does anyone know what this "arm" does that connects the driven LFA element to the boom?

Attachment:
8elLFA3.jpg
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Thanks!


Thu Dec 07, 2017 12:17 am
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 G0KSC Antenna Query 
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Post Re: G0KSC Antenna Query
The bar is a 1/4 wave matching stub, Pawsey stub it's called,

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Thu Dec 07, 2017 3:22 am
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 G0KSC Antenna Query 
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Thanks, I assume that this will mean that not (ugly) balun or choke is required?


Thu Dec 07, 2017 11:11 am
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 G0KSC Antenna Query 
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Personally never needed a choke balun at these frequencies/antenna types.

If the cats hair stands on end when you key up, fit one

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Thu Dec 07, 2017 11:17 am
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 G0KSC Antenna Query 
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Haha thank you.


Thu Dec 07, 2017 11:45 am
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 G0KSC Antenna Query 
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Post Re: G0KSC Antenna Query
From Justin's website.

Pawsey Stub

19/11/2010 Many Hams have seen inconsistencies with the Pawsey stub, largely believed to be due to the varied velocity factor seen in most coax cables. Steve, G3TXQ contacted me with a very interesting viewpoint and provided some seemingly valid information explaining why only coax of the same type should be used for the Pawsey stub, not a separate, dissimilar wire. I therefore would no longer recommend this style of Pawsey stub but will keep the information here. My antenna balun with a feedpoint choke may give the best, all round performance: http://www.hamradio.me/antennas/coax-ve ... #more-1528

Cheers

Tony

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Thu Dec 07, 2017 12:58 pm
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 G0KSC Antenna Query 
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Post Re: G0KSC Antenna Query
I did see that earlier today, thank you.

I could remove it altogether and use a coax choke - will leave enough coax to allow.


Thu Dec 07, 2017 4:02 pm
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