> Having at last found time to study the recent, and most
interesting, "Two
> Wire Beverage thread" I cannot find the answer to one
particularly
> interesting question:
> How close should one put the wires in a two wire Beverage
system?
The short answer is as close as you can space the wires. The
ideal situation is where wire common mode and differential
mode impedances are near equal.
300 ohm TV lead-in and 450 ohm window ladder line both work
very well. This is what I have always used, and what most of
the people I know use. I'm just not patient enough to build
a long close-spaced line when I can buy a bulk roll of two
wire line for a very reasonable price.
Using a prefabricated line with close or continuous spacers
allows you to twist the line, and this helps maintain
balance. This will allow the system to be very good even on
20 meters. It also is a heck of a lot less work.
DX Engineering sells a complete assembly for the feedpoint
and termination that works with ladder line, so you don't
even have to build that part if you don't want to. I think
the more complicated the overall system, the less time
people want to spend building it.
73 Tom
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