Topband: Matching transformer phasing Question
zedkay at bellsouth.net
Sat Mar 3 16:46:10 EST 2007
This may seem like a silly question at first, but I can't seem to
logic my way through it and arrive at a satisfying answer, so I'm
asking for additional insight.
Does it make any difference which winding "end" of a Beverage
matching transformer attaches to the coax shield and which to the
center conductor? In all the schematics, it seems pretty
straightforward - "hot" end of the Hi-Z winding oriented to
correspond to the center conductor attachment of the secondary Lo-Z
winding, and "cold" grounded end of the Hi-Z winding corresponding to
the coax braid attachment of the Lo-Z winding. This is easy to
visualize with a toroidal core, perhaps less so with a binocular core.
If the orientation of the winding ends is spatially inverted, does it
also invert the phase of the output signal by 180 degrees? If so,
does this even matter in this application (single Beverage, not part
of a phased pair)?
The question only arose because I had made several printed circuit
boards for matching and switching two-wire, bi-directional
Beverages. One layout uses the "correct" winding orientation, while
the other uses the "inverted" scheme. The correct layout works fine;
the inverted one has not been tested "in the field", only on the
workbench. I wanted to ask for other opinions before I install the
"inverted phase" unit, and possibly save myself some frustration (and
a lot of walking).
Charles - K5ZK
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