Hi Dave,
> After doing some experimenting with 2 wire beverages (and having some
funny
> things happening and some trouble) I have a question. Which direction of
> arriving signal is supposed to come out which port on the matching
> transformer? Victor Misek's 2nd edition Beverage Antenna Handbook and
John
> Devoldere's 2nd edition of Low-Band DXing would seem to be in direct
> disagreement.
I've heard that before, but never found where they disagree. One seems to
be a copy of the other.
1.) The center tap of the transformer at the feedpoint contains the common
mode signal at that end. The common mode signal is the signal you get when
the two wires of the antenna are in parallel, so that means it is just like
you connected to the wire as a long wire at that point.
It will fire AWAY from the feedpoint at that connection point when the
receiver is attached there, and that is the point you must terminate when
reversing.
2.) The push-pull connection (through the secondary winding) is the
differential mode connection. It makes the two wire Beverage act like a
feedline connected to the far end.
3.) This is the important part. The far end of the antenna needs a
reflection transformer. Grounding one wire, and letting the other float,
WILL NOT make the antenna behave properly. It is impossible to get full
performance when using that system, unless the antenna is VERY long. Always
use a good reflection transformer that is impedance matched to the antenna.
The theory that grounding one wire and floating the other results in proper
reflection topology is absolutely wrong, even though it did originally
come from Beverage.
73 Tom trouble shoot my system so it would be helpful to know which
> way it is supposed to properly work.
>
> 73. . . Dave
> W0FLS
>
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