[SCCC] Phased verticals

[Bill Shell - N6WS]

Bob,

I built a phase switching and matching box for my 160m phased verticals, 
and the matching was pretty easy.  I match the 50-Ohm to the 25-Ohm pair 
of antennas by using a transformer with a 14-turn primary (50-Ohm) and 
10-turn secondary (25-Ohm).  You can see it on my Webpage:
https://www.n6ws.com/projects/

The Phasing Switch Box is the third picture.  The transformer is in the 
lower-left of the photo.

You should also consider a common-mode choke, which you can see in the 
fourth picture right below the switch box.

To be honest, I'm not sure I see much performance increase in the 
parallel (broadside) mode of the two verticals.  I know it models to 
show some gain, but where I see the best performance is when I switch in 
the 90-deg delay-line to provide gain to the East or West.  My "East" is 
actually 73-deg Azimuth.  When I am working Europe on 160m, I have 
better performance by selecting East instead of North-South.  Which 
North-South is both verticals in parallel with no delay-line.  Even as 
far North as when I am working Zone 16 station, I think East is better 
than North-South. I may be wrong, because it is hard to pick out the 
best performance when you have a lot of QSB on the signal, but that is 
just my feeling.

I have never tried just using a T-connector to combine the antennas, so 
I can't help you there.  The UN-22-25 may be a good solution for you.  I 
have a little trouble believing their 2kW peak power rating in such a 
small box, but...

I hope my explanation helps you in your antenna work.

73, Bill
N6WS


On 8/12/2019 6:24 PM, Bob Grubic wrote:
> I am considering using two 20-meter phased verticals for some portable
> operations. (Later, two 40-meter verticals.)
>
> Keeping it simple at first, I'd run coax from my rig to a T-connector and
> then through identical, same length pieces of coax to each vertical
> (driving them in phase). I've seen this scenario several times online, but
> the fact that two 50-ohm antennas would be in parallel at the T-connector
> to give you a 25-ohm load (in effect), somehow bothers me.
>
> I've seen an article online suggesting using an UNUN to match the rig's
> coax to the two legs feeding the antennas--essentially replacing the
> T-connector (with a UN-22-25 from CWS). http://www.cwsbytemark.com/  I
> can't find any other discussion of this particular subject online.
>
> Has anyone had any experience with this or thoughts on the subject? I'd
> appreciate hearing about it.
>
> Thanks very much.
>
> 73,
> Bob NC6Q
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