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 SHF branded 70cm 19 element yagi query/problem 
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Post SHF branded 70cm 19 element yagi query/problem
I am trying to get one of these SHF branded beams refurbished.

I have concerns about the driven element connections. The connection box has a pcb to connect the feed to with a thin coax (balun?) between the main driven element feeds (gamma match?). Driven element looks like a folded dipole but the driven side is thinner and shorter so looks like some sort of matching.

Currently has lowest SWR at 443MHz which is odd (yes I checked the analyser with a working 70cm beam), the connections on the little pcb seem odd, the coax centre is clamped to the centre pcb pad, but this has a tag underneath which looks like to is meant to touch/short to the boom bolt, seems a bit of an unreliable connection, plus there is a thin wire connection from coax centre to one of the driven element feed points.

This means the coax centre connects to boom and one of the element feedpoints. I don't have any instructions nor managed to find any on the web.

Anybody got one of these or similar SHF branded aerial or instructions that might help working out how this should be connected.

Hopefully the pics below will help with the query.

Thanks


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Mon Jun 10, 2019 10:52 am
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 SHF branded 70cm 19 element yagi query/problem 
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Post Re: SHF branded 70cm 19 element yagi query/problem
Any ideas?


Mon Jun 17, 2019 9:53 pm
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 SHF branded 70cm 19 element yagi query/problem 
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Post Re: SHF branded 70cm 19 element yagi query/problem
You haven't shown a picture of the inside of the junction box with the board out, so half the story is missing!

At a guess, I would think that the tag you mention does nothing, probably should be folded flat under the board, and the two screws that clamp the coax connect the outer coax to the boom.

You have also described the driven element, but again no picture :)

Both of those pictures would help to see what it is likely to be.

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Tue Jun 18, 2019 5:00 am
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 SHF branded 70cm 19 element yagi query/problem 
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Post Re: SHF branded 70cm 19 element yagi query/problem
I've now had the required information sent to me and got the aerial working, thanks


Thu Jun 20, 2019 7:56 pm
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 SHF branded 70cm 19 element yagi query/problem 
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Post Re: SHF branded 70cm 19 element yagi query/problem
chrisf wrote:
I've now had the required information sent to me and got the aerial working, thanks


What was it?

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Thu Jun 20, 2019 8:17 pm
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 SHF branded 70cm 19 element yagi query/problem 
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Post Re: SHF branded 70cm 19 element yagi query/problem
Vargarda Radio


Sun Jun 23, 2019 3:14 pm
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 SHF branded 70cm 19 element yagi query/problem 
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Post Re: SHF branded 70cm 19 element yagi query/problem
chrisf wrote:
Vargarda Radio


I meant what were the connections :)

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Sun Jun 23, 2019 3:21 pm
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