Gary,
Yep.. it applies to reactance.. but I am not quite sure that the 1:1 is
working and I need to run the swr curve on the antenna to verify if it is
correct or not. I agree it was a little hard to figure out what ON4UN was
trying to say and the fact that I was not going to use the exact core he was
advocating made the problem worse. But what was even worse was some of the
bad formulae in the original Misek book.. ugh! It didnt track some of the
stuff currently in use by the guys.
The beverage is partially over a stream and the resistance of the earth is
really good so I have initially only installed one 4 ft ground rod at each
end. I have two more to install at the feed end.
Thanks again
Jim
----- Original Message -----
From: "Gary Nichols" <kd9sv@comcast.net>
To: wa3mej@comcast.net
Sent: Friday, December 2, 2011 9:53:08 AM
Subject: RE: Topband: Beverage up but maybe has problems comments requested
Jim, the 4X rule is referring to the "reactance" of the windings and NOT the
turns ratio. Your reflection transformer should probably be a 1:1 ratio
with the primary center tapped and connected to the secondary which the
other end goes to ground. A good ground is necessary at both ends of the
antenna. The information in ON4UN's book is accurate although very
confusing...de gary, kd9sv
-----Original Message-----
From: topband-bounces@contesting.com [mailto:topband-bounces@contesting.com]
On Behalf Of wa3mej@comcast.net
Sent: Friday, December 02, 2011 10:32 PM
To: topband@contesting.com
Subject: Topband: Beverage up but maybe has problems comments requested
OK the Beverage is up, transformers installed, and coax hooked up. Let me
refresh everyone’ memory - I put up a 490 ft window line beverage which
turns out to be headed 30deg magnetic (best I could do on short notice) and
it has a termination transformer as opposed to the open/short termination.
I have noticed several things:
1. I am not impressed with the front to back. I don’t think it is all it
should be but I have not measured it.
2. Although I did work YN2CC last night I have not heard but one station
from Europe .
3. There appears to be some discrimination off the side of the antenna.
The 8’s, 9’s etc are down as much as 20db.
Having said all of this I started rereading all of the literature and think
I may have discovered a problem with my transformers. I noticed that some
calculated the transformers based directly on the impedance of the line/
surge z. By this I mean they calculated the transformer turns based
directly on say 50 ohms for the primary and 450 ohms for the secondary.
When I designed my transformers I used the rule of 4 like is done with broad
band transformers so that the turns would be calculated on 200 ohms for the
primary and 1800 ohms for the secondary. DID I ERR?????? This might be
why there is no front to back like there should be and maybe even the why I
can’t seem to hear the Europeans.
Luckily changing the transformers is an easy task.
Comments please !
Jim WA3MEJ
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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